Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3543
PID: SID 115
SPN: 4094
FMI: 31

Description: NOx Limits Exceeded Due to Insufficient Reagent Quality – Condition Exists
Troubleshooting:
Reason:
NOx Limits Exceeded Due to Insufficient Reagent Quality – Condition Exists. The diesel
exhaust fluid quality is not sufficient enough to provide adequate NOx reduction.
Effect:
Possible reduced engine performance.
Circuit Description:
The engine control module (ECM) monitors the NOx concentration in the engine’s exhaust
gases using an aftertreatment intake NOx sensor and an aftertreatment outlet NOx sensor. By
comparing these two values, the ECM is able to determine the conversion efficiency of the
SCR catalyst and dosing system.
Component Location:
The SCR catalyst is located in the vehicle’s exhaust system, after the diesel particulate filter
and decomposition tube.
Conditions for Running the Diagnostics:
This diagnostic runs after the diesel exhaust fluid tank has been refilled. Specific engine and
aftertreatment conditions must be met. NOx sensor data is gathered over varying engine
speeds and loads. When enough data has been gathered, the diagnostic will run, make a
pass/fail decision, and begin to gather data again.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the NOx conversion across the SCR catalyst was
less than expected, and the diesel exhaust fluid tank has recently been refilled.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) Engine torque will be severely reduced.
Conditions for Clearing the Fault Code:
It is necessary to use the “Reset All Faults” command in INSITE™ electronic service tool to
clear this fault and extinguish the amber CHECK ENGINE lamp and/or Malfunction Indicator
Lamp (MIL).
Shop Talk:
Troubleshoot all other active NOx sensor and SCR dosing system related fault codes before
this fault.
Possible Causes:
1) Malfunctioning diesel exhaust fluid dosing system
2) Exhaust system leaks
3) Malfunctioning SCR catalyst
4) Degraded, diluted, or incorrect diesel exhaust fluid
5) Diesel exhaust fluid deposits in the decomposition tube

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3683
PID: SID 27
SPN: 1127
FMI: 7

Description: Engine Turbocharger 1 Boost Pressure – Mechanical System Not Responding or
Out of Adjustment
Troubleshooting:
Reason:
Engine Turbocharger 1 Boost Pressure – Mechanical System Not Responding or Out of
Adjustment.
Effect:
Possible reduced engine performance
Circuit Description:
The variable geometry turbocharger (VGT) is electronically activated by the VGT actuator. The
VGT actuator is a smart device and receives information via the J1939 data link from the
primary engine control module (ECM). The VGT actuator performs its own diagnostics and
reports malfunctions back to the primary engine ECM, using the J1939 data link. The ECM
then decodes the error message and converts it to a fault code.
Component Location:
The VGT actuator is located on the turbocharger bearing housing.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running.
Conditions for Setting the Fault Codes:
The Variable Geometry Turbocharger (VGT) actuator position could not meet the commanded
position for greater than 10 seconds.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or Malfunction Indicator Lamp
(MIL) after the diagnostic fails on two consecutive trips.
2) The VGT actuator will continue to attempt to meet the commanded position.
3) Active and stationary regeneration of the diesel particulate filter will be disabled.
4) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
5) Diesel exhaust fluid injection into the aftertreatment system is disabled.
6) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The ECM will turn off the amber CHECK ENGINE lamp and/or MIL immediately after the
diagnostic runs and passes.
3) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults.
Shop Talk:
N/A
Possible Causes:
1) A malfunctioning turbocharger actuator
2) A malfunctioning turbocharger

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3724
PID: 168
SPN: 168
FMI: 17

Description: Battery 1 Voltage – Data Valid But Below Normal Operating Range – Least Severe
Level
Troubleshooting:
Reason:
Battery 1 Voltage – Data Valid But Below Normal Operating Range – Least Severe Level. Low
voltage to the EGR valve device driver has been detected.
Effect:
Possible reduced engine performance.
Circuit Description:
The EGR valve device driver in the ECM provides power to the EGR valve motor. The EGR
valve motor is used to move the EGR valve to the correct position, as commanded by the
ECM.
Component Location:
The EGR valve device driver is internal to the ECM and can not be serviced separately.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine
is running.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected low power at the EGR valve device driver. The
ECM was no longer able to control the EGR valve.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
This fault code indicates an internal failure in the ECM
Possible Causes:
1) Inactive fault codes
2) Faulty ECM

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 4163
PID: N/A
SPN: 5742
FMI: 16

Description: Aftertreatment Diesel Particulate Filter Temperature Sensor Module – Data Valid
But Above Normal Operating Range – Moderately Severe Level
Troubleshooting:
Reason:
Aftertreatment Diesel Particulate Filter Temperature Sensor Module- Data Valid But Above
Normal Operating Range – Moderately Severe Level. High internal temperature detected in the
aftertreatment diesel particulate filter temperature sensor module.
Effect:
Possible reduced engine performance
Circuit Description:
The aftertreatment diesel particulate filter temperature sensor module is a smart device that
communicates with the engine control module via the J1939 data link. The aftertreatment
diesel partculate filter temperature sensor module performs its own internal diagnostics and
reports malfunctions back to the engine control module using the J1939 data link. The
aftertreatment diesel particulate filter temperature sensor module is used to measure the
aftertreatment diesel oxidation catalyst intake temperature, aftertreatment diesel particulate
filter intake temperature, and aftertreatment diesel particulate filter outlet temperature. The
temperature probes are permanently attached to the aftertreatment diesel particulate filter
temperature sensor module and can not be replaced individually.
Component Location:
The aftertreatment diesel particulate filter temperature sensor module is mounted on the
aftertreatment diesel particulate filter.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine
is running.
Conditions for Setting the Fault Codes:
The aftertreatment diesel particulate filter temperature sensor module reported the internal
circuit board temperature was too high.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or Malfunction Indicator Lamp
(MIL) after the diagnostic fails on two consecutive trips.
2) Active and stationary regeneration of the diesel particulate filter will be disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
This fault code indicates the internal temperature of the aftertreatment diesel particulate filter
temperature sensor module was too high. Troubleshoot the exhaust system for leaks, missing
heat shields, or dirt and debris that could lead to over heating of the aftertreatment diesel
particulate filter temperature sensor module.
Possible Causes:
1) Inactive fault codes
2) Faulty aftertreatment DPF temperature sensor module
3) Faulty ECM

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3235
PID: N/A
SPN: 4363
FMI: 16

Description: Aftertreatment SCR Outlet Temperature – Data Valid But Above Normal Operating
Range – Moderately Severe Level
Troubleshooting:
Reason:
Aftertreatment SCR Outlet Temperature – Data Valid But Above Normal Operating Range –
Moderately Severe Level. The SCR outlet temperature sensor reading has exceeded the
maximum temperature limit.
Effect:
Possible reduced engine performance.
Circuit Description:
The aftertreatment SCR (selective catalytic reduction) temperature sensor module is a smart
device that communicates with the engine control module via the J1939 data link. The
aftertreatment SCR temperature sensor module performs its own internal diagnostics and
reports malfunctions back to the engine control module using the J1939 data link. The
aftertreatment SCR temperature sensor module is used to measure the aftertreatment SCR
intermediate temperature and aftertreatment SCR outlet temperature. The temperature probes
are permanently attached to the aftertreatment SCR temperature sensor module and can not
be replaced individually.
Component Location:
The aftertreatment SCR temperature sensor module is mounted on the aftertreatment SCR
catalyst.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running and active regeneration of the
aftertreatment diesel particulate filter is not occurring.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the temperature at the SCR catalyst outlet
temperature sensor was greater than 650°C [1202°F] for more than 60 seconds.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the red STOP ENGINE lamp immediately after the diagnostic runs and
fails.
2) Diesel exhaust fluid injection into the aftertreatment system is disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the red STOP ENGINE lamp immediately after the diagnostic runs and
passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
This fault will go inactive immediately after the SCR outlet temperature drops below the
warning limit, and will likely be inactive when the vehicle is in the shop. For these reasons this
troubleshooting tree must be used for both active and inactive fault codes.
Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring
supplied by the OEM.
For intermittent power supply and datalink communication issues with Aftertreatment
Components, it is highly recommended that the OEM Power Distribution Center fuses and
relays be thoroughly checked for loose, missing or intermittent connections.
Possible Causes:
1) Malfunctioning SCR catalyst
2) Degraded, diluted, or incorrect diesel exhaust fluid
3) Malfunctioning in-range SCR outlet temperature sensor

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3255
PID: N/A
SPN: 3246
FMI: 0

Description: Aftertreatment Diesel Particulate Filter Outlet Temperature – Data Valid But Above
Normal Operating Range – Moderately Severe Level
Troubleshooting:
Reason:
Aftertreatment Diesel Particulate Filter Outlet Temperature – Data Valid But Above Normal
Operating Range -Moderately Severe Level. The aftertreatment diesel particulate filter outlet
temperature sensor reading has exceeded the maximum engine protection temperature limit.
Effect:
Progressive power and/or speed derate increasing in severity from time of alert. If the Engine
Protection Shutdown feature is enabled, the engine will shut down 30 seconds after the red
STOP lamps starts flashing.
Circuit Description:
The aftertreatment diesel particulate filter temperature sensor module is a smart device that
communicates with the engine control module via the J1939 data link. The aftertreatment
diesel partculate filter temperature sensor module performs its own internal diagnostics and
reports malfunctions back to the engine control module using the J1939 data link. The
aftertreatment diesel particulate filter temperature sensor module is used to measure the
aftertreatment diesel oxidation catalyst intake temperature, aftertreatment diesel particulate
filter intake temperature, and aftertreatment diesel particulate filter outlet temperature. The
temperature probes are permanently attached to the aftertreatment diesel particulate filter
temperature sensor module and can not be replaced individually.
Component Location:
The aftertreatment diesel particulate filter outlet temperature sensor is located in the
aftertreatment system. It is located at the outlet of the aftertreatment diesel particulate filter.
Refer to the original equipment manufacturer (OEM) service manual.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running and active regeneration of the
aftertreatment diesel particulate filter is not occurring.
Conditions for Setting the Fault Codes:
The aftertreatment diesel particulate filter intake temperature sensor reading was greater than
687°C [1269°F] for 90 seconds.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the red STOP ENGINE lamp immediately after the diagnostic runs and
fails.
2) Active and stationary regeneration of the diesel particulate filter will be disabled.
3) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
4) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
5) The engine will be shut down if the Engine Protection Shutdown feature is enabled.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the red STOP ENGINE lamp immediately after the diagnostic runs and
passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
This fault will go inactive immediately after the aftertreatment temperatures drop below the
warning limit, and will likely be inactive when the vehicle is in the shop. For these reasons, this
troubleshooting tree must be used for both active and inactive fault codes.
Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring
supplied by the OEM.
Possible Causes:
1) Excessive engine oil or diesel fuel being introduced into the exhaust system from the engine
2) A damaged engine fuel injector causing unburned diesel fuel to enter the exhaust system
3) A face plugged aftertreatment diesel oxidation catalyst

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3385
PID: 105
SPN: 105
FMI: 1

Description: Intake Manifold 1 Temperature – Data Valid But Below Normal Operational Range –
Moderately Severe Level
Troubleshooting:
Reason:
Intake Manifold 1 Temperature – Data Valid But Below Normal Operational Range – Moderately
Severe Level. The intake manifold temperature is below a critical threshold
Effect:
None on performance.
Circuit Description:
The Engine Control Module (ECM) provides 5 volts to the intake manifold temperature signal
circuit, and monitors the change in voltage caused by changes in the resistance of the sensor
to determine the intake manifold temperature. When the intake air is cold, the sensor (or
thermistor) resistance is high. The ECM signal voltage only pulls down a small amount through
the sensor to a ground. Therefore, the ECM senses a high signal voltage or low temperature.
When the intake air is warm, the sensor resistance is low. The signal voltage pulls down a
large amount. Therefore, the ECM senses a low signal voltage, or a high temperature.
Component Location:
The intake manifold 1 pressure/temperature sensor is located in the air intake horn.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is operating at idle.
Conditions for Setting the Fault Codes:
The intake manifold temperature was less than 20°C [68°F] while the engine was idleing for an
extended period of time.
Action Taken When the Fault Code is Active:
The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs
and fails.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
The EGR valve was closed because the engine was idling with cold intake manifold
temperatures for an extended period of time.
Possible Causes:
1) Inactive fault codes
2) Faulty ECM

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3541
PID: N/A
SPN: 51
FMI: 4

Description: Engine Intake Throttle Actuator Position Sensor Circuit – Voltage Below Normal or
Shorted to Low Source
Troubleshooting:
Reason:
Engine Intake Throttle Actuator Position Sensor Circuit – Voltage below normal, or shorted to
low source. Low signal voltage detected at the engine intake air throttle position sensor circuit.
Effect:
Possible reduced engine performance
Circuit Description:
The engine control module (ECM) controls the engine intake air throttle actuator. The ECM can
open and close the throttle based on the operating condtions in order to regulate air flow to the
engine.
Component Location:
The engine intake air throttle actuator is mounted in the piping between the charge air cooler
and intake manifold.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine
is running.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the engine intake air throttle position sensor circuit
voltage was out of range low.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) Engine intake air throttle actuation will be disabled. The engine intake air throttle will default
to the open position.
3) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
4) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) A malfunctioning engine intake air throttle position sensor
2) A short circuit to ground in the engine harness
3) An open circuit in the engine harness

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 2962
PID: 412
SPN: 412
FMI: 16

Description: Exhaust Gas Recirculation Temperature – Data Valid But Above Normal
Operational Range – Moderately Severe Level
Troubleshooting:
Reason:
Exhaust Gas Recirculation Temperature – Data Valid But Above Normal Operational Range –
Moderately Severe Level. EGR temperature has exceeded the engine protection limit.
Effect:
Possible reduced engine performance.
Circuit Description:
The exhaust gas recirculation (EGR) temperature sensor is a variable resistor sensor and is
used to measure the temperature of the EGR gas flow after it exits the EGR cooler. The engine
control module (ECM) supplies 5 volts to the EGR temperature signal circuit. The ECM
monitors the change in voltage caused by changes in the resistance of the sensor to determine
the EGR flow temperature. The EGR temperature value is used by the ECM for the engine
protection system and engine emissions control.
Component Location:
The EGR temperature sensor is located on the EGR connection tube between the EGR cooler
and the air intake connection.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine
is running.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the EGR temperature was greater than 250°C
[482°F] for more than 5 seconds.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic
runs and fails.
2) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
Note: This fault code will most likely not be active with no load in the shop. The engine must be
loaded to trigger this fault code
Possible Causes:
1) A fouled EGR cooler
2) Plugged or restricted EGR differential pressure sensor ports
3) A damaged EGR valve
4) A low reading from the EGR differential pressure sensor
5) A low reading for the EGR valve position sensor
6) High exhaust temperatures
7) Low coolant level
8) High coolant temperature
9) An incorrect coolant/water mixture
10) A stuck closed variable geometry turbocharger

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3137
PID: N/A
SPN: 5019
FMI: 4

Description: Engine Exhaust Gas Recirculation Outlet Pressure Sensor Circuit – Voltage Below
Normal or Shorted to Low Source
Troubleshooting:
Reason:
Engine Exhaust Gas Recirculation Outlet Pressure Sensor Circuit – Voltage Below Normal or
Shorted to Low Source. Low signal voltage detected at the EGR orifice pressure sensor.
Effect:
Possible reduced engine performance.
Circuit Description:
The engine control module (ECM) provides a 5 volt supply to the EGR orifice pressure sensor
on the sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The
EGR orifice pressure sensor provides a signal to the ECM on the EGR orifice pressure sensor
signal circuit. This sensor signal voltage changes based on the pressure at the EGR orifice
pressure sensor.
Component Location:
The EGR orifice pressure sensor is mounted on the EGR mass measurement assembly near
the EGR differential pressure sensor.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine
is running.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the EGR orifice pressure sensor signal voltage
was less than 0.25 volts for 5 seconds.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) Signal circuit open or shorted to ground in the engine harness or sensor
2) Supply line open or shorted to ground

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 3228
PID: N/A
SPN: 3216
FMI: 2

Description: Aftertreatment 1 Intake NOx Sensor – Data Erratic, Intermittent, or Incorrect
Troubleshooting:
Reason:
Aftertreatment Intake NOx Sensor – Data Erratic, Intermittent, or Incorrect. An incorrect NOx
sensor reading has been detected by the aftertreatment intake NOx sensor.
Effect:
Possible reduced engine performance.
Circuit Description:
The aftertreatment intake NOx (nitrogen oxides) sensor is a smart device and communicates
with the engine control module (ECM) via the J1939 data link. The aftertreatment intake NOx
sensor performs internal diagnostics and reports malfunctions back to the primary ECM using
the J1939 data link. The NOx sensor is permanently attached to the NOx control module. They
are serviced as a single component and can not be replaced individually. The aftertreatment
intake NOx sensor is used to measure the NOx emissions at the intake of the aftertreatment
system.
Component Location:
The aftertreatment intake NOx sensor is mounted on the engine near the turbocharger turbine
outlet.
Conditions for Running the Diagnostics:
This diagnostic runs when the aftetreatment diesel oxidation catalsyst intake temperature
sensor has been above 150° C [302° F] for 5 seconds while the engine is running. This
diagnostic has to meet specific engine and aftertreatment conditions to run and complete
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the aftertreatment intake NOx reading was higher
or lower than the calculated aftertreatment intake NOx value for the engine operating
conditions.
Action Taken When the Fault Code is Active:
The ECM illuminates the amber CHECK ENGINE lamp and/or Malfunction Indicator Lamp
(MIL) after the diagnostic fails on two consecutive trips.
Conditions for Clearing the Fault Code:
1) To validate the repair, it may be necessary to operate the vehicle on a chassis dynamometer
or to drive the vehicle in order to get the engine load high enough for the diagnostic to run.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) EGR system leaks
2) Exhaust system leaks
3) An incorrectly installed aftertreatment intake NOx sensor
4) An aftertreatment intake NOx sensor that has carbon buildup on the tip of the sensor
5) A malfunctioning EGR differential pressure sensor.
6) A malfunctioning EGR valve
7) Excessive oil consumption
8) Possible engine misfire
9) The NOx sensor part number is incorrect
Page

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 2646
PID: 110
SPN: 110
FMI: 14

Description: Engine Coolant Temperature – Condition Exists
Troubleshooting:
Reason:
Engine Coolant Temperature – Condition Exists. The EGR valve was closed to reduce engine
coolant temperature.
Effect:
Possible reduced engine performance.
Circuit Description:
The coolant temperature sensor is a variable resistor sensor and is used to measure the
temperature of the coolant of the engine. The engine control module (ECM) supplies 5 volts to
the coolant temperature signal circuit. The ECM monitors the change in voltage caused by
changes in the resistance of the sensor to determine the coolant temperature.
Component Location:
The engine coolant temperature sensor is located on the thermostat housing.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the engine coolant temperature was above a
threshold and closed the EGR valve to reduce the engine coolant temperature.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic
runs and fails.
2) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, and leave the key in the ON position for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
When the engine coolant temperature nears the engine protection limits, the EGR valve will be
closed to reduce the coolant temperature. This fault code is used as an information fault code,
only indicating that the EGR valve has closed. No malfunction has occurred to cause this fault
code. Other engine protection fault codes will be active if the engine coolant temperature has
exceeded the engine protection limits.
Possible Causes:
1) Inactive fault codes
2) Faulty ECM

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 2764
PID: 131
SPN: 1209
FMI: 16

Description: Exhaust Gas Pressure – Data Valid but Above Normal Operating Range –
Moderately Severe Level
Troubleshooting:
Reason:
Exhaust Gas Pressure – Data Valid but Above Normal Operating Range – Moderately Severe
Level. High exhaust gas pressure has been detected by the exhaust gas pressure sensor.
Effect:
Possible reduced engine performance
Circuit Description:
The exhaust gas pressure sensor is used to measure exhaust gas pressure in the exhaust
manifold. This information is used by the engine control module (ECM) to control emissions
and exhaust gas recirculation (EGR) valve operation. The ECM provides a 5 volt supply to the
exhaust gas pressure sensor on the sensor supply circuit. The ECM also provides a ground on
the sensor return circuit. The exhaust gas pressure sensor provides a signal to the ECM on the
exhaust gas pressure sensor signal circuit. This sensor signal voltage changes, based on the
pressure in the exhaust manifold.
Component Location:
The exhaust gas pressure sensor is located above the front section of the exhaust manifold
and is plumbed into the exhaust manifold.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the engine is running.
Conditions for Setting the Fault Codes:
Exhaust gas pressure sensor reading was greater that the engine protection limits
Action Taken When the Fault Code is Active:
An engine derate will be activated to bring exhaust gas pressure below the maximum operating
limits.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) A malfunctioning variable geometry turbocharger
2) A damaged in-range exhaust gas pressure sensor
3) A plugged or restricted aftertreatment diesel particulate filter
4) A plugged or restricted EGR cooler

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 2878
PID: SID 381
SPN: 4097
FMI: 7

Description: Aftertreatment Fuel Drain Valve – Mechanical System Not Responding or Out of
Adjustment
Troubleshooting:
Reason:
Aftertreatment Fuel Drain Valve – Mechanical System Not Responding Properly or Out of
Adjustment. The aftertreatment fuel shutoff drain valve has been detected to be stuck closed.
Effect:
Active aftertreatment diesel particulate filter regeneration will be disabled.
Circuit Description:
The aftertreatment fuel drain valve is used to relieve the fuel pressure in the aftertreatment fuel
injector supply line. Before active regeneration of the aftertreatment DPF, a diagnostic test on
the system is performed. The aftertreatment fuel injector opens and relieves fuel pressure in
the line. The aftertreatment fuel pressure sensor must be reading atmospheric pressure at this
point in the test. The aftertreatment fuel drain valve closes. The aftertreatment fuel shutoff
valve and aftertreatment fuel injector then close and trap the fuel between the aftertreatment
fuel shutoff valve and the aftertreatment fuel injector. The diagnostic checks to make sure the
system maintains fuel pressure.
Component Location:
The aftertreatment fuel drain valve is located in the aftertreatment fuel shutoff manifold.
Conditions for Running the Diagnostics:
This diagnostic runs during active regeneration of the aftertreatment diesel particulate filter.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected a stuck closed aftertreatment fuel drain valve
when the aftertreatment fuel pressure does not change after the aftertreatment fuel drain valve
is commanded open.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic
runs and fails.
2) Active regeneration of the aftertreatment diesel particulate filter will be disabled unitl the next
key cycle.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
To validate the repair, perform the INSITE™ electronic service tool Aftertreatment Diesel
Particulate Filter Regeneration Test. Once the temperatures in the aftertreatment are warm
enough to inject diesel fuel into the exhaust, the diagnostic will run.
1) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
2) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes. The Reset All Faults command in INSITE™ electronic service tool can be used to
clear active and inactive faults.
Shop Talk:
N/A
Possible Causes:
1) A stuck closed aftertreatment fuel drain valve
2) A plugged or restricted fuel drain line

Make: Cummins

Engine: ISL9 CM2350 (2013-17)

Fauld Code: 2274
PID: 411
SPN: 411
FMI: 4

Description: Exhaust Gas Recirculation Differential Pressure Sensor Circuit – Voltage Below
Normal or Shorted to Low Source
Troubleshooting:
Reason:
Exhaust Gas Recirculation Valve Delta Pressure Sensor Circuit – Voltage Below Normal or
Shorted to Low Source. Low signal voltage detected at the EGR differential pressure sensor
circuit.
Effect:
Possible reduced engine performance
Circuit Description
The exhaust gas recirculation (EGR) differential pressure sensor has two ports that sense
exhaust pressure. The sensor outputs a voltage which represents the pressure difference
between the two ports located across an orifice in the EGR tube. The engine control module
(ECM) uses this pressure to determine how much exhaust gas is flowing in the EGR
connection tube to the intake manifold. This information is used to control the EGR valve for
correct emission levels.The ECM provides a 5 volt supply to the EGR differential pressure
sensor on the sensor supply circuit. The ECM also provides a ground on the sensor return
circuit. The EGR differential pressure sensor provides a signal to the ECM on the EGR
differential pressure sensor signal circuit. This sensor signal voltage changes, based on the
differential pressure in the EGR crossover tube.The EGR differential pressure sensor
measures the exhaust gas pressure drop across the EGR differential pressure orifice. This
pressure drop is used to calculate the amount of EGR flow into the intake manifold.
Component Location:
The EGR Valve and EGR Differential Pressure Sensor location varies depending on engine
model.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine
is running.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the EGR differential pressure signal voltage was
less than 0.26 VDC for more than 8 seconds.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) A default value for the EGR differential pressure sensor is used.
3) Diesel exhaust fluid injection into the aftertreatment system is disabled.
4) Active and stationary regeneration of the diesel particulate filter will be disabled.
5) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
6) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) A signal circuit open or shorted to ground in the engine harness or sensor
2) A supply wire open or shorted to ground
3) A malfunctioning EGR differential pressure sensor

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 2376
PID: 412
SPN: 412
FMI: 4

Description: Exhaust Gas Recirculation Temperature Sensor Circuit – Voltage Below Normal or
Shorted to Low Source
Troubleshooting:
Reason:
Exhaust Gas Recirculation Temperature Sensor Circuit – Voltage Below Normal or Shorted to
Low Source. Low signal voltage detected at EGR temperature circuit
Effect:
Possible reduced engine performance.
Circuit Description:
The exhaust gas recirculation (EGR) temperature sensor is a variable resistor sensor and is
used to measure the temperature of the EGR gas flow after it exits the EGR cooler. The engine
control module (ECM) supplies 5 volts to the EGR temperature signal circuit. The ECM
monitors the change in voltage caused by changes in the resistance of the sensor to determine
the EGR flow temperature.
The EGR temperature value is used by the ECM for the engine protection system and engine
emissions control.
Component Location:
The EGR temperature sensor is located on the EGR connection tube between the EGR cooler
and the air intake connection.
Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine
is running.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the EGR temperature signal voltage was less than
0.05-VDC for more than 8 seconds.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) A default value for the exhaust gas recirculation temperature reading is used.
3) Diesel exhaust fluid injection into the aftertreatment system is disabled.
4) Active and stationary regeneration of the diesel particulate filter will be disabled.
5) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
6) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
The EGR temperature sensor shares return wires in the engine harness with other sensors. An
open return can cause multiple fault codes to be active.
Possible Causes:
1) A signal shorted to ground in the harness
2) A signal shorted to return or ground in the sensor

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 2554
PID: 131
SPN: 1209
FMI: 2

Description: Exhaust Gas Pressure 1 – Data Erratic, Intermittent, or Incorrect
Troubleshooting:
Reason:
Exhaust Gas Pressure – Data Erratic, Intermittent or Incorrect. The exhaust gas pressure
sensor is reading an erratic value.
Effect:
Possible reduced engine performance
Circuit Description:
The exhaust gas pressure sensor is used to measure exhaust gas pressure in the exhaust
manifold. This information is used by the engine control module (ECM) to control emissions
and exhaust gas recirculation (EGR) valve operation. The ECM provides a 5 volt supply to the
exhaust gas pressure sensor on the sensor supply circuit. The ECM also provides a ground on
the sensor return circuit. The exhaust gas pressure sensor provides a signal to the ECM on the
exhaust gas pressure sensor signal circuit. This sensor signal voltage changes, based on the
pressure in the exhaust manifold.
Component Location:
The exhaust gas pressure sensor is located above the front section of the exhaust manifold
and is plumbed into the exhaust manifold.
Conditions for Running the Diagnostics:
This diagnostic consists of two parts:
One part runs immediately after the keyswitch is turned OFF, and the engine coolant
temperature is above 70°C or 158°F. The second part runs continuously while the engine is
running.
Conditions for Setting the Fault Codes:
1) The Engine Control Module (ECM) detected the exhaust pressure reading was higher or
lower than the other absolute pressure sensors when the keyswitch is OFF and the engine is
not running.
2) The Engine Control Module (ECM) detected the exhaust pressure was higher or lower than
expected during normal engine operation.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) A default value is used for the exhaust gas pressure sensor reading.
3) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
4) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, first ensure the engine coolant temperature is above 70°C or 158° F.
Operate the engine if necessary.
2) Cycle the keyswitch to the ON position for 30 seconds, then cycle the keyswitch to the OFF
position for 30 seconds. Start the engine and run it at high idle for up to 5 minutes.
3) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
4) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
5) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
6) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) Stuck in-range exhaust gas pressure sensor reading
2) High resistance in the exhaust gas pressure sensor signal or return lines
3) Plugging or restriction in the exhaust gas pressure sensor tube
4) Leaks in the exhaust system

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 1896
PID: SID 146
SPN: 2791
FMI: 13

Description: EGR Valve Controller – Out of Calibration
Troubleshooting:
Reason:
EGR Valve Controller – Out of Calibration. The EGR valve has failed the automatic calibration
procedure at initial key ON.
Effect:
Possible reduced engine performance
Circuit Description:
The exhaust gas recirculation (EGR) valve is controlled by a brushless motor located on top of
the EGR valve. The EGR valve motor uses three different motor legs to move the valve
through its range of motion. The ECM uses the EGR motor A, B, and C wires to command the
EGR valve to the appropriate position in order to meet EGR flow targets.The EGR valve motor
contains three position sensors that detect the location of the EGR valve. These sensors report
the position of the valve back to the ECM over the EGR valve position A, B, and C wires.
Component Location:
The EGR Valve and EGR Differential Pressure Sensor location varies depending on engine
model.
Conditions for Running the Diagnostics:
This diagnostic runs at initial key ON and occasionally during normal engine operation after the
EGR valve is commanded closed.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the EGR valve failed the autozero span check.
Action Taken When the Fault Code is Active
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) Exhaust Gas Recirculation (EGR) valve operation will be disabled.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle and leave the key in the ON position for 2
minutes. Then start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
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Diagnostic Trouble Code Solutions 16/12/2024 15:25:03
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
When the keyswitch is initially turned ON and at various times during engine operation, the
closed position of the EGR valve is checked. This diagnostic checks to make sure the EGR
valve is not stuck open. The EGR valve will close when the fault code is active. The fault code
will remain active until the next key cycle. The aftertreatment system must be inspected after
making the appropriate repair outlined in this fault code troubleshooting tree. Progressive
damage to the aftertreatment system may have occurred. Perform the Snap-Acceleration Test
to check for a malfunctioning diesel particulate filter.
Possible Causes:
1) Inactive fault codes
2) Faulty ECM

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 1925
PID: SID 334
SPN: 3482
FMI: 2

Description: Aftertreatment Fuel Shutoff Valve – Data Erratic, Intermittent, or Incorrect
Troubleshooting:
Reason:
Aftertreatment Fuel Shutoff Valve 1 – Data Erratic, Intermittent, or Incorrect. An error has been
detected in the aftertreatment fuel shutoff valve or the aftertreatment fuel injector system.
Effect:
Possible reduced engine performance
Circuit Description:
Before active regeneration of the aftertreatment DPF, a diagnostic test on the system is
performed. The aftertreatment fuel injector opens and relieves fuel pressure in the line. The
aftertreatment fuel pressure sensor must be reading atmospheric pressure at this point in the
test. The aftertreatment fuel drain valve closes. The aftertreatment fuel shutoff valve and
aftertreatment fuel injector then close and trap the fuel between the aftertreatment fuel shutoff
valve and the aftertreatment fuel injector. The diagnostic checks to make sure the system
maintains fuel pressure.
Component Location:
The aftertreatment fuel injector is installed in the exhaust system in the turbocharger adapter
pipe. The aftertreatment fuel pressure sensor and aftertreatment fuel shutoff valve are installed
in the shutoff valve manifold.
Conditions for Running the Diagnostics:
This diagnostic runs during active regeneration of the aftertreatment diesel particulate filter.
Conditions for Setting the Fault Codes:
The engine control module (ECM) detected an internally leaking aftertreatment fuel shutoff
valve.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) Active regeneration of the aftertreatment diesel particulate filter will be disabled unitl the next
key cycle.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, start the engine and perform the INSITE™ electronic service tool
Aftertreatment Diesel Particulate Filter Regeneration Test.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) Internal leak of the aftertreatment fuel shutoff valve allowing fuel pressure to leak past the
shutoff valve
2) Stuck closed, plugged, or clogged aftertreatment fuel injector

Make: Cummins
Engine: ISL9 CM2350 (2013-17)

Fauld Code: 1932
PID: SID 382
SPN: 3556
FMI: 2

Description: Aftertreatment Doser – Data Erratic, Intermittent, or Incorrect
Troubleshooting:
Reason:
Aftertreatment Doser – Data Erratic, Intermittent, or Incorrect. An internal or external fuel leak
has been detected in the aftertreatment fuel system.
Effect:
Possible reduced engine performance
Circuit Description:
Before active regeneration of the aftertreatment DPF, a diagnostic test on the system is
performed. The aftertreatment fuel injector opens and relieves fuel pressure in the line. The
aftertreatment fuel pressure sensor must be reading atmospheric pressure at this point in the
test. The aftertreatment fuel drain valve closes. The aftertreatment fuel shutoff valve and
aftertreatment fuel injector then close and trap the fuel between the aftertreatment fuel shutoff
valve and the aftertreatment fuel injector. The diagnostic checks to make sure the system
maintains fuel pressure.
Component Location:
The aftertreatment fuel injector is installed in the exhaust system in the turbocharger adapter
pipe. The aftertreatment fuel pressure sensor and aftertreatment fuel shutoff valve are installed
in the shutoff valve manifold.
Conditions for Running the Diagnostics:
This diagnostic runs during active regeneration of the aftertreatment diesel particulate filter.
Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected a leaking aftertreatment fuel injector or an external
leak.
Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator
Lamp (MIL) immediately when the diagnostic runs and fails.
2) Active regeneration of the aftertreatment diesel particulate filter will be disabled unitl the next
key cycle.
3) Engine torque will be reduced if the engine is operated for an extended period of time with
this fault active.
Conditions for Clearing the Fault Code:
1) To validate the repair, start the engine and perform the INSITE™ electronic service tool
Aftertreatment Diesel Particulate Filter Regeneration Test.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE
immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs
and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator
Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear
active and inactive faults, as well as extinguish the MIL for OBD applications.
Shop Talk:
N/A
Possible Causes:
1) A stuck open or leaking aftertreatment fuel injector
2) An external leak in the aftertreatment fuel injector system.
3) A leaking aftertreatment fuel shutoff manifold

Make: Cummins
Engine: ISM CM876 (2007-09)

Fauld Code: 2961
PID: 412
SPN: 412
FMI: 0

Description: EGR Temperature – Data Valid But Above Normal Operating Range – Least Severe
Level. EGR temperature has exceeded the engine protection limit.
Troubleshooting:
Verify the ECM calibration is correct. Check the calibration revision history found on
QuickServe® Online for applicable fixes to the calibration stored in the ECM. If necessary,
recalibrate the ECM.
Possible causes:
1)Malfunctioning EGR differential pressure tubes
2)A damaged EGR valve
3)A stuck open turbocharger control valve
4)A low reading from the EGR differential pressure sensor
5)A low reading for the EGR valve position sensor
6)High exhaust temperatures
7)Low coolant level
8)High coolant temperature
9)An incorrect coolant/water mixture
10)A stuck closed variable geometry turbocharger
11)A fouled EGR cooler.
NOTE: This fault code will most likely not be active with no load in the shop. The engine must
be loaded to trigger this fault code.
Possible repairs:
1)Replace the exhaust gas recirculation temperature sensor.
2)Drain the coolant and fill the cooling system with the proper mixture.
3)Tighten or replace the exhaust gas recirculation differential pressure sensor tubes.

Make: Cummins
Engine: ISM CM876 (2007-09)

Fauld Code: 2962
PID: 412
SPN: 412
FMI: 0

Description: Exhaust Gas Recirculation Temperature – Data Valid but Above Normal
Operational Range – Moderately Severe Level. EGR temperature has exceeded the engine
protection limit.
Troubleshooting:
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision
history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If
necessary, recalibrate the ECM.
Possible causes:
1)A fouled EGR cooler.
2)Failed EGR differential pressure tubes.
3)A failed EGR valve.
4)A stuck open turbocharger control valve.
5)A low reading from the EGR differential pressure sensor.
6)A low reading for the EGR valve position sensor.
7)High exhaust temperatures.
8)Low coolant level.
9)High coolant temperature.
10)An incorrect coolant/water mixture.
11)A stuck closed variable geometry turbocharger.
Note: This fault code will most likely not be active with no load in the shop. The engine must be
loaded to trigger this fault code.
Possible repairs:
1)Replace the EGR temperature sensor.
2)Drain the coolant and refill the cooling system with the proper mixture.
3)Tighten or replace the EGR differential pressure sensor tubes.
4)Clear the debris or replace the EGR differential pressure tube.

Make: Cummins
Engine: ISM CM875 (2003-06)

Fauld Code: 2964
PID: P105
SPN: 105
FMI: 0/16

Description: Intake Manifold 1 Temperature – Data Valid But Above Normal Operating Range –
Least Severe Level. Intake manifold air temperature signal indicates intake manifold air
temperature is above engine protection warning limit.
Troubleshooting:
The intake manifold air temperature sensor measures the temperature of the charge air (fresh
air compressed by the turbocharger, cooled by the charge air cooler, and mixed with EGR) as it
passes through the intake manifold. This fault code is activated if the intake manifold air
temperature is above 121°C [250° F] for five seconds.
NOTE: Prior to running the INSITE™ electronic service tool EGR Valve and EGR
Valve/Turbocharger Operational Test, the ECM Calibration Software Phase could possibly
need to be updated to the latest Software Phase. The ECM Calibration Phase Software can be
checked in INSITE™ electronic service tool, under ‘Features and Parameters’. Expand the
selection for ‘System ID and Dataplate and go to ‘Calibration Information’. If the Software
Phase is earlier than shown below, calibrate the ECM using the January 2006 INCAL™ CDROM,
or later. Engines with the Software Phase listed below or later do not require a
calibration.
ISX engines with CM870 (engines built after January 2004) require Software Phase 06050302.
ISX engines with CM870 (engines built before January 2004) require no changes at this time.
This is a warrantable calibration change.
Possible causes:
1)Plugged charge air cooler fins
2)Restricted airflow through the charge air cooler
3)Damaged EGR differential pressure sensor, or leaks in sensor tubes
4)Undersized charge air cooler
5)High turbocharger compressor outlet temperature
6)Fouled EGR cooler
7)Stuck EGR valve
8)Sensor malfunction.
Possible repairs:
1)Replace the intake manifold temperature sensor.

Make: Cummins
Engine: ISM CM875 (2003-06)

Fauld Code: 2359
PID: P411
SPN: 411
FMI: 0/16

Description: EGR Differential Pressure Sensor – Data Valid but Above Normal Operating Range
– Moderately Severe Level. EGR differential pressure sensor failed automatic calibration
procedure or EGR differential pressure reading not valid for engine operating conditions.
Troubleshooting:
Update: Prior to running INSITE™ electronic service tool, verify that the ECM has the correct
Calibration Software Phase. There have been changes in the calibrations that reduce false
occurrences of the fault code and also affect the tolerable sensor range.
The ECM Calibration Software Phase can be checked in INSITE™ electronic service tool,
under Features and Parameters.
1)Expand the selection for System ID and Dataplate, then go to Calibration Information.
2)ISX Engines with CM870 built during and after January 2004 require software phase
06050402 or greater from the February 2007 INCAL™ DVD or newer.
3)ISX Engines with CM870 built before January 2004 require software phase 05050000 or
greater from the April 2007 INCAL™ DVD or newer.
The ECM Calibration Revision History can be found at:
http://insite.cummins.com/insite/tools/incal/index.html
This is a warrantable calibration change.
Possible causes:
1)A plugged or leaking low or high EGR differential pressure tubes
2)A damaged EGR differential pressure sensor
3)A stuck open or closed EGR valve
4)A damaged EGR connection tube hose
5)A leak in the EGR connection tube hoses or tubes
6)A damaged variable geometry turbocharger
7)A damaged variable geometry actuator
8)A damaged turbocharger control valve
9)A damaged turbocharger control shutoff valve
10)A plugged turbocharger control shutoff valve filter
11)A leak in the air line supplying air pressure to the turbocharger control shutoff valve,
turbocharger control valve, or variable geometry actuator
12)Incorrectly installed EGR differential pressure tubes
13)Incorrectly installed EGR differential pressure sensor
14)Expanded exhaust gases trapped in differential pressure tube
15)A damaged EGR cooler that allows coolant into the crossover tube and EGR differential
pressure sensor tubes.
If Fault Code 2359 is active after a key cycle and the engine is not running, it will be set
inactive only if the following conditions are met:
1)Engine coolant temperature is greater than 67°C [153°F]
2)Intake manifold air temperature is greater than 7°C [45°F]
3)Keyswitch transitions from ON to OFF for 30 seconds
4)EGR differential pressure sensor reading is within a set calibration threshold near zero.
Possible repairs:
1)Tighten any loose connections and clean the battery terminals.
2)Tighten the fittings, replace the EGR differential pressure tube and the adapter, or correct the
exhaust leaks.
3)Install the EGR differential pressure tubes correctly.
4)If coolant is found in the EGR differential pressure sensor tubes, they must be replaced.
5)Install the EGR differential pressure sensor correctly.
6)Tighten the differential pressure tube fittings.
7)Replace the EGR valve.
8)Repair leaks.
9)Replace the turbocharger control valve.
10)Replace the turbocharger assembly.
11)Replace the turbocharger actuator.
12)Repair the air supply from the OEM air tanks.
13)Replace the turbocharger.

Make: Cummins
Engine: ISM CM875 (2003-06)

Fauld Code: 2376
PID: P412
SPN: 412
FMI: 4/4

Description: Recirculated Exhaust Gas Temperature Sensor Circuit – Voltage Below Normal or
Shorted to Low Source. Low signal voltage detected at EGR temperature circuit.
Troubleshooting:
Beginning with ESN 14039654, the temperature sensor return circuit was separated from the
pressure sensor return circuit. For ESNs prior to this and with engine wiring harness Part
Number 3682854, refer to the Common Pressure/Temperature Sensor Return Circuit above.
For this ESN and greater or for any other engine wiring harness part number, refer to the
Separate Pressure/Temperature Sensor Return Circuit above.
This fault code is set active if the sensor signal voltage is below the normal operating range for
the sensor and the ECM has commanded the EGR valve open. This fault code will not be set
active if the ECM has commanded the EGR valve closed. However, once the fault code is set,
it will remain active independent of whether the EGR valve is open or closed.
The EGR temperature sensor shares return wires in the engine harness with other sensors. A
shorted return can cause multiple fault codes to be active. Before troubleshooting Fault Code
2376, check for multiple fault codes.
Possible causes:
1)Signal shorted to ground in the harness or ECM
2)Signal shorted to return or ground in the sensor.
Possible repairs:
1)Replace the EGR temperature sensor.
2)Replace the ECM.
3)Repair or replace the engine harness.

Make: Cummins
Engine: ISM CM876 (2007-09)

Fauld Code: 2754
PID: 81
SPN: 81
FMI: 16

Description: Engine Particulate Filter Inlet Pressure – Data Valid but Above Normal Operational
Range – Moderately Severe Level. Excessive black smoke has been detected exiting the
engine and entering the aftertreatment diesel particulate filter.
Troubleshooting:
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision
history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If
necessary, recalibrate the ECM.
Possible causes:
1)Boost leaks in the charge air cooler plumbing
2)A malfunctioning variable geometry turbocharger (VGT)
3)A malfunctioning exhaust gas recirculation (EGR) valve
4)A malfunctioning in-range EGR differential pressure sensor
5)A malfunctioning in-range boost pressure sensor
6)A malfunctioning in-range barometric pressure sensor
7)A cylinder misfire or overfueling.
Possible repairs:
1)Repair or replace the leaking component.
2)Clean or replace the charge air cooler.
3)Replace the intake manifold pressure/temperature sensor.
4)Replace the barometric pressure sensor
5)Tighten the fittings, or replace the EGR differential pressure tube.
6)Replace the EGR differential pressure sensor adapter.
7)lace the injector if necessary.

Make: Cummins
Engine: ISM CM876 (2007-09)

Fauld Code: 2322
PID: SID 64
SPN: 723
FMI: 2

Description: Engine Camshaft Speed/Position Sensor – Data Erratic, Intermittent, or Incorrect.
Camshaft engine speed sensor intermittent synchronization.
Troubleshooting:
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision
history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If
necessary, calibrate the ECM.
During engine operation, the ECM monitors the secondary speed sensor (camshaft speed
sensor) signal. Fault Code 778 will become active and light the yellow lamp if the signal from
the secondary speed sensor is not present or degraded for more than 3 continuous seconds. If
over a period of time the ECM detects several incidents of a loss of the secondary speed
sensor signal, but the signal loss is short in duration, this fault code will become active. Since
the secondary engine speed signal is not used for normal engine operation, a vehicle operator
should not notice any symptoms related to this problem.
This fault code becomes active whenever the ECM detects a persistent loss of the secondary
engine speed sensor signal over a short period of time.
This fault becomes inactive at each key ON or if the ECM does not detect a loss of the
secondary engine speed sensor signal for at least 20 minutes.
Failures that can cause this fault:
1)Intermittent loss of primary speed sensor signal; the most likely cause is an intermittent open
or short circuit that can be experienced with speed sensor connector problems.
2)Sensor air gap that is marginally too small or too large, or target wheel exhibits excessive
runout.
Actions to take if this fault is intermittent:
1)Look for intermittent engine harness connections in the secondary engine speed sensor
circuit.
2)Look for loose connections at the ECM connector where the pins can not be locked into the
socket.
3)Look for places where the engine harness has worn into a nearby component causing an
intermittent short circuit.
4)Look for pin wear at the speed sensor.
5)Inspect the target wheel for damage.
Possible repairs:
1)Repair or replace the engine harness.
2)Replace or shim the sensor if air gap is out of specification. If the target runout is excessive,
replace the target.
3)Replace the engine camshaft speed/position sensor.

Make: Cummins
Engine: ISM CM875 (2003-06)

Fauld Code: 2346
PID: N/A
SPN: 2789
FMI: 0/15

Description: Turbocharger Turbine Intake Temperature – Data Valid But Above Normal
Operating Range – Least Severe Level. Turbocharger turbine intake temperature has exceeded
the engine protection limit.
Troubleshooting:
The most common cause of this fault code is low boost. Low boost can be caused by several
factors: leaking charge air cooler, loose charge air cooler clamps, malfunctioning components,
(including charge air cooler piping or hoses), intake manifold pressure sensor, variable
geometry turbocharger, turbocharger control valve, or turbocharger control shutoff valve.
NOTE: Prior to running INSITE™ electronic service tool EGR valve and EGR
valve/turbocharger operational test, the ECM Calibration software phase could possibly need
to be updated to the latest software phase. The ECM calibration phase software can be
checked in INSITE™ electronic service tool, under ‘Features and Parameters’. Expand the
selection for ‘System ID and Dataplate’ and go to ‘Calibration Information’. If the software
phase is earlier than shown below, recalibrate the ECM using the January 2006 INCAL™ CDROM,
or later. Engines with the software phase listed below or later do not require a
recalibration.
ISX engines with CM870 (engines built after January 2004) require software phase 06050402.
ISX engines with CM870 (engines built before January 2004) require software phase
05050000.
This is a warrantable calibration change.
This fault code can also be caused be a Turbocharger Fuel Control (TFC) derate which can be
viewed in INSITE™ electronic service tool, under the User Fueling State. TFC derates can be
caused by several factors: high exhaust temperatures, high turbocharger compressor inlet
temperatures, and high turbocharger compressor outlet temperatures.
NOTE: The engine must be loaded to trip this fault code and to determine if the problem has
been found and fixed. It is possible to cause the fault code to log when the engine is placed on
a dynamometer. The fault code will trip because of the stationary nature and high temperatures
encountered on the dynamometer.
Possible repair:
1)Use the INCAL™ Calibration DVD-ROM with the proper calibration software phase to
calibrate the ECM.
2)The engine power output was derated to limit the exhaust temperatures. This is normal
operation. No repairs are necessary.
3)Repair air leaks.
4)Replace the turbocharger assembly.
5)Replace the turbocharger control valve.
6)Repair the air supply from the OEM air tanks.
7)Replace the turbocharger control shutoff valve filter.
8)Replace the turbocharger control shutoff valve.
9)Replace the variable geometry turbocharger.

Make: Cummins
Engine: ISM CM876 (2007-09)

Fauld Code: 2357
PID: SID 146
SPN: 2791
FMI: 7

Description: EGR Valve Control Circuit – Mechanical System Not Responding Properly or Out
of Adjustment. The EGR motor has exceeded the duty cycle limit, indicating a stuck open EGR
valve.
Troubleshooting:
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision
history found on Quickserve™ Online for applicable fixes to the calibration stored in the ECM.
If necessary, recalibrate the ECM.
This fault code is triggered when the EGR valve motor is unable to move the EGR valve in the
open position. This is normally caused by a restriction in the EGR valve not allowing the EGR
valve to move to the commanded position.
The fault code will be inactive at key-on. It will only go active if the EGR valve is commanded
open and the EGR valve is unable to move to the commanded position.
The ECM calibration contains an automatic EGR valve override test. Thirty seconds after
turning the keyswitch on, the EGR valve all be commanded open to 60 percent and will be held
in this position for 1 minute and then it will be commanded to 0 percent open. Turn the
keyswitch off for 20 seconds and then turn the keyswitch on and read the fault codes. If Fault
Code 1896 is active, this indicates that the EGR valve is stuck in the open position.
The aftertreatment system must be inspected after making the appropriate repair outlined in
this fault code troubleshooting tree. Progressive damage to the aftertreatment system may
have occurred. Perform the Snap Acceleration Test to check for a damaged diesel particulate
filter.
Possible repairs:
1)Replace the EGR valve motor.
2)Replace the EGR valve.
3)Replace the damaged aftertreatment component

Make: Cummins
Engine: ISM CM876 (2007-09)

Fauld Code: 1935
PID: SID 146
SPN: 2791
FMI: 11

Description: EGR Actuator Driver Circuit – Root Cause Not Known. Intermittent communication
between the smart EGR valve controller and the ECM has been detected.
Troubleshooting:
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision
history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If
necessary, recalibrate the ECM.
This fault code is logged when the EGR valve controller did not receive valid J1939 commands
from the primary engine ECM. Intermittent J1939 datalink connections or interference on the
J1939 network are possible causes of this fault code. Also check for intermittent power supply
and ground connections to the EGR valve controller.
Possible repairs:
1)Repair or replace the engine harness.
2)Replace the EGR valve motor.
3)Replace the ECM.

Make: Cummins
Engine: ISM CM875 (2003-06)

Fauld Code: 2215
PID: P094
SPN: 94
FMI: 1/18

Description: Fuel Pump Delivery Pressure – Data Valid But Below Normal Operating Range –
Moderately Severe Level. Low fuel pressure has been detected by the ECM.
Troubleshooting:
Verify the electronic control module (ECM) calibration is correct.
It is possible to swap the connections between the aftertreatment fuel pressure sensor and the
fuel delivery pressure sensor. If this occurs, Fault Code 2215 will intermittently go active and
the engine will run rough and will surge at low idle. If these symptoms are present, make sure
the fuel pressure connections are connected properly.
The fuel pressure is monitored by the electronic control module (ECM). If the rail fuel pressure
is lower than an acceptable level for given engine operating conditions, the fault code is
logged.
Possible causes:
1)A damaged or sticking drain-back valve located in the fuel supply circuit in the integrated fuel
system module (IFSM) which is located directly above the fuel lift pump.
Possible repairs:
1)Properly connect the aftertreatment fuel pressure sensor and fuel delivery pressure sensor
wiring harness connections.
2)Prime the fuel system.
3)Fill the fuel tanks.
4)Repair or replace the fuel lift pump.
5)Repair or replace the fuel shutoff valve.
6)Replace the 1724 kPa [250 psi] regulator.
7)Use the following procedure in the Signature™, ISX, and QSX15 Service Manual, Bulletin
3666239 for repair or replacement of the fuel pump (gear pump).
8)Locate and repair the source of the air leak by checking all the OEM supply lines and fittings,
suction-side fuel filter head, fuel tank stand pipes, ECM cooling plate, and ECM cooling plate
fuel supply and return lines.
9)Replace the suction-side fuel filter or repair the cause of high inlet restriction.
10)Replace the pressure fuel filter.
11)Replace the regulator.
12)For ISX CM871 and ISM CM876 engines, use the following procedure for replacement of
the rail fuel pressure sensor.

Make: Cummins
Engine: ISM CM876 (2007-09)

Fauld Code: 2274
PID: 411
SPN: 411
FMI: 4

Description: Exhaust Gas Recirculation Valve Delta Pressure Sensor Circuit – Voltage Below
Normal, or Shorted to Low Source. Low signal voltage detected at the EGR differential
pressure sensor circuit.
Troubleshooting:
Verify the electronic control module (ECM) calibration is correct. Check the calibration revision
history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If
necessary, recalibrate the ECM.
Possible causes:
1)A signal circuit open or shorted to ground in the engine harness or sensor.
2)A supply wire open or shorted to ground.
3)A malfunctioning EGR differential pressure sensor.
Possible repairs:
1)Replace the EGR valve delta pressure sensor.
2)Replace the ECM.
3)Repair or replace the engine harness.