Symptom Chart

WARNING: This page is about a different variant/trim than selected.

SYMPTOM CHART

Condition	Possible Sources	Action
No communication with the Trailer Brake Control (TBC) module	Fuse(s) Wiring, terminals or connectors TBC module	REFER to MODULE COMMUNICATIONS NETWORK to diagnose the no communication problem.
Without a trailer connected to the vehicle and with the ignition key turned to the RUN position, the TBC module display does not light up/prove out	Fuse(s) Wiring, terminals or connectors TBC module	NOTE: The TBC module will not prove out if the battery voltage is above 16 volts or below 9 volts. GO to PINPOINT TEST B .
Without a trailer connected to the vehicle and with the ignition key turned to the RUN position, the TBC module display lights up/proves out, but does not light up afterward (will not illuminate with input from the gain + button or slide lever)	Instrument Cluster (IC) not configured for TBC system	REFER to DTC U2202 in the Trailer Brake Control (TBC) Module DTC Chart .
When the ignition key is turned to the RUN position, the TBC module display does light up/prove out but the trailer brakes are inoperative	Fuse(s) Wiring, terminals or connectors TBC module Customer trailer	GO to PINPOINT TEST D .
The trailer brakes are always engaged	Wiring, terminals or connectors TBC module Customer trailer	GO to PINPOINT TEST E .
The message center intermittently displays TRAILER DISCONNECTED or WIRING FAULT ON TRAILER while towing a trailer	Wiring, terminals or connectors Customer trailer	GO to PINPOINT TEST E .
The message center displays TBC FAULT	DTCs present IC not configured for TBC system	RETRIEVE and RECORD the DTCs. GO to the Trailer Brake Control (TBC) Module DTC Chart . If no DTCs are present in the TBC module, REFER to DTC U2202 in the Trailer Brake Control (TBC) Module DTC Chart .
The message center displays TRAILER FAULT	Wiring, terminals or connectors TBC module Customer trailer	GO to PINPOINT TEST C .