Make: Detroit
Engine: DD15 GHG17 (2017 & Newer)
PID: N/A
SPN: 3226
FMI: 20
Description: Selective Catalyst Reduction Outlet NOx Sensor – Drive Low
Troubleshooting:
DESCRIPTION:
Selective catalyst reduction (SCR) outlet NOx sensor – drift low.
MONITORED PARAMETER:
Engine out NOx.
TYPICAL ENABLING CONDITIONS:
The following must be true for greater than 30s:
1. Fuel mass is 0.
2. Diesel particulate filter (DPF) outlet temperature greater than 200°C (392°F).
3. Battery voltage greater than 10V.
4. Engine speed 500 to 2100 rpm.
MONITOR SEQUENCE:
None
EXECUTION FREQUENCEY:
Always enabled
TYPCIAL DURATION:
Five seconds
DASH LAMPS:
MIL
ENGINE REACTION:
None
VERIFICATION:
Parked regeneration
POSSIBLE CUASES:
1. Exhaust leaks in the Aftertreatment System (ATS).
2. Damaged ATS.
3. Faulty SCR outlet NOx sensor.
Make: Detroit
Engine: DD15 GHG17 (2017 & Newer)
PID: N/A
SPN: 3226
FMI: 21
Description: NOx Outlet Sensor Drift High
Troubleshooting:
DESCRIPTION:
NOx outlet sensor drift high.
MONITORED PARAMETER:
Selective Catalyst Reduction (SCR) Outlet NOx.
TYPICAL ENABLING CONDITIONS:
Coolant temperature greater than 70°C (158°F), engine rpm greater than 1500 and torque
greater than 80%.
MONITOR SEQUENCE:
None
EXECUTION FREQUENCEY:
Continuous when enabling conditions met.
TYPCIAL DURATION:
20 seconds
DASH LAMPS:
MIL
ENGINE REACTION:
None
VERIFICATION:
Parked regeneration
POSSIBLE CUASES:
1. Exhaust leaks in the Aftertreatment System (ATS).
2. Damaged ATS.
3. Diesel fuel or oil contamination.
4. DEF tank and the DEF system may need cleaning/flushing.
5. Faulty DEF Dosing unit.
6. Faulty SCR outlet NOx sensor.
Make: Detroit
Engine: DD15 GHG17 (2017 & Newer)
PID: N/A
SPN: 3227
FMI: 2
Description: Lambda Reading Rationality Check
Troubleshooting:
DESCRIPTION:
Goal of this diagnostic is to detect the tail pipe out lambda signal lower than expected in engine
no fueling mode.
MONITORED PARAMETER:
Outlet NOx sensor.
TYPICAL ENABLING CONDITIONS:
1. Engine at 1200 to 2400 rpm.
2. Averaged SCR temperature greater than 240°C (464°F).
3. In DEF dosing mode.
4. Coolant temp above 65°C (149°F).
5. Ambient air temp above -18°C (0°F).
6. Ambient pressure above 752 mbar (10.9 psi).
7. Not in EGR Mode.
8. Not in regen mode.
MONITOR SEQUENCE:
Outlet NOx sensor.
EXECUTION FREQUENCEY:
Continuous when enabling conditions met.
TYPCIAL DURATION:
10 seconds
DASH LAMPS:
MIL
ENGINE REACTION:
None
VERIFICATION:
Road test at operating temperature with engine above 1200 rpm, above 40% load, in DEF
dosing mode. Not in regen or EGR mode.
POSSIBLE CAUSES:
1. ACM software needs update.
2. Faulty Outlet NOx sensor.
Make: Detroit
Engine: DD15 GHG17 (2017 & Newer)
PID: N/A
SPN: 3227
FMI: 3
Description: Selective Catalyst Reduction Outlet NOx Sensor Circuit Failed High
Troubleshooting:
DESCRIPTION:
This code sets when there is a short to power on the SCR outlet NOx circuit between the
sensor and ECU.
MONITORED PARAMETER:
SCR Outlet NOx sensor.
TYPICAL ENABLING CONDITIONS:
Dewpoint enabled
MONITOR SEQUENCE:
None
EXECUTION FREQUENCEY:
Continuous when enabling conditions met.
TYPCIAL DURATION:
3 seconds
DASH LAMPS:
1. MIL
2. CEL
ENGINE REACTION:
10% derate
VERIFICATION:
Parked regen
POSSIBLE CAUSES:
1. Bent pins.
2. Spread pins.
3. Corroded pins.
4. Faulty SCR Outlet NOx sensor.