Pinpoint Test A: No Communication With The Trailer Brake Control (TBC) Module
WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Use the flex probe kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.
- A1 CHECK THE MISSING CONTROLLER AREA NETWORK (CAN) SOURCE IDENTIFIER PID
- Key in ON position.
- Enter the following diagnostic mode on the scan tool: Missing CAN Source Identifier PID.
- Does the PID indicate a missing module?
- Yes
: For missing powertrain control module (PCM), REFER to ELECTRONIC ENGINE CONTROLS - GASOLINE ENGINES
(gasoline engine) or ELECTRONIC ENGINE CONTROLS - DIESEL ENGINE
(diesel engine).
For missing anti-lock brake system (ABS) control module, REFER to ANTI-LOCK CONTROL .
For missing instrument cluster, REFER to INSTRUMENT CLUSTER .
- No : GO to A2.
- A2 CHECK THE VOLTAGE TO THE TBC MODULE
- Key in OFF position.
- Disconnect: TBC Module C2142a.
- Disconnect: TBC Module C2142b.
- Key in ON position.
- Measure the voltage between TBC module, harness side and ground as follows:
- TBC module C2142a-1, circuit 50 (RD), harness side.
- TBC module C2142b-3, circuit 298 (VT/OG), harness side.
- Are the voltages greater than 10 volts?
- Yes : GO to A3.
- No
: VERIFY CJB fuse 101 (30A) is OK. If OK, REPAIR circuit 50 (RD) for an open.
VERIFY CJB fuse 28 (10A) is OK. If OK, REPAIR circuit 298 (VT/OG) for an open.
CLEAR the DTCs. REPEAT the self-test.
- A3 CHECK GROUND CIRCUIT 206 (WH) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between TBC module C2124a-4, circuit 206 (WH), harness side and ground.
- Is the resistance less than 5 ohms?
- Yes : REFER to MODULE COMMUNICATIONS NETWORK to continue diagnosis of the communication network.
- No : REPAIR circuit 206 (WH) for an open. CLEAR the DTCs. REPEAT the self-test.