Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC C0870 00
- Device Voltage Reference Output 1 Circuit
DTC C1112 00
- Trailer Brake Control Relay Low Control Circuit
DTC C1113 01
- Trailer Brake Control Relay High Control Circuit Short to Battery
DTC C1114 00
- Trailer Brake Control Solenoids Control Circuit
DTC C1119 00
- Trailer Brake Control Relay Feedback Circuit
Diagnostic Fault Information
Circuit/System Description
The trailer brake control relay receives inputs from the fuel pump/trailer brake control module, these inputs are used to determine the amount of
voltage the relay will supply to the trailer brakes.
Conditions for Running the DTC
* Ignition ON.
* Battery voltage is 9.5-17 V.
* The module is powered up and completes initialization.
Conditions for Setting the DTC
C0870 00
The trailer brake circuit reference voltage for the trailer brake control relay is below 4.8 V or above 5.2 V.
C1112 00
* The fuel pump/trailer brake control module detects a short to ground, open or a short to voltage on the integrated trailer brake relay control
active low circuit.
* The fuel pump/trailer brake control module detects an open in the battery positive voltage circuit to the trailer brake control relay.
* The fuel pump/trailer brake control module detects an open in the ground circuit to the trailer brake control relay.
* The fuel pump/trailer brake control module detects a short to ground or open in the solid state relay enable circuit.
C1113 01
* The fuel pump/trailer brake control module detects a short to voltage in the solid state relay enable circuit.
* The fuel pump/trailer brake control module detects a short to voltage in the trailer brake output supply voltage control circuit.
C1114 00
The fuel pump/trailer brake control module detects a short to ground, open or a short to voltage on the solid state relay output circuit.
