* Trailer Brake Control Relay Replacement (1500) (See: Accessories and Optional Equipment/Towing / Trailer System/Trailer Towing
Relay/Service and Repair/Trailer Brake Control Relay Replacement (1500))Trailer Brake Control Relay Replacement (2500) (See:
Accessories and Optional Equipment/Towing / Trailer System/Trailer Towing Relay/Service and Repair/Trailer Brake Control Relay
Replacement (2500))
* Trailer Brake Control Module Replacement (See: Accessories and Optional Equipment/Towing / Trailer System/Trailer Brake Control
Module/Service and Repair/Trailer Brake Control Module Replacement)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for TBCM replacement, setup, and programming
Gasoline Without LY6
DTC C0870, C1112, C1113, C1114, or C1119 (Gasoline Without LY6)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
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.
