Make: International
Engine: MaxxForce DT (2010 & Newer)
PID: N/A
SPN: 3511
FMI: 3

Description: VREF 3 voltage above maximum
Troubleshooting:
The Reference Voltage (VREF) circuit is a 5-volt reference point supplied to the Electronic
Control Module (ECM). It also provides power to all 3-wire sensors.
Probable causes:
1) VREF circuit short to PWR

Make: International
Engine: MaxxForce DT (2010 & Newer)
PID: N/A
SPN: 3511
FMI: 4

Description: VREF 3 voltage below minimum
Troubleshooting:
The Reference Voltage (VREF) circuit is a 5-volt reference point supplied to the Electronic
Control Module (ECM). It also provides power to all 3-wire sensors.
Probable causes:
1) VREF circuit short to GND
2) Failed sensor causing short to GND on VREF circuit

Make: International
Engine: MaxxForce DT (2010 & Newer)
PID: N/A
SPN: 3512
FMI: 14

Description: DCU VREF 1 or 2 voltage above or below normal
Troubleshooting:
The Doser Control Unit (DCU) supplies volatge to the Aftertreatment Pressure 1 and 2 sensors.
Probable causes:
1) DCU VREF circuit short to PWR
2) DCU VREF circuit short to GND
3) Failed sensor causing short to GND on VREF circuit

Make: International
Engine: MaxxForce DT (2010 & Newer)
PID: N/A
SPN: 3556
FMI: 0

Description: AFT Fuel Pressure 2 below Warning Pressure
Troubleshooting:
The purpose of the Aftertreatment (AFT) System is to catalyze carbon monoxide (CO), Oxides
of Nitrogen (NOx), and Hydrocarbons (HC). The Diesel Particulate Filter (DPF) will capture
soot and other particulates exiting the exhaust pipe. Once the DPF is full, it is heated and the
soot trapped inside is burned more efficiently than an exhaust system without an AFT system.
Probable causes:
1) Hydrocarbon injector assembly failure (plugged)
2) Biased Aftertreatment (AFT) fuel pressure 2 sensor or circuit