Test F: The Trailer Brake Controller Does Not Respond to the Diagnostic Tool
PINPOINT TEST F: THE TRAILER BRAKE CONTROLLER DOES NOT RESPOND TO THE DIAGNOSTIC TOOLF1-F2:
F2-F3:
Normal Operation
The trailer brake controller communicates with the diagnostic tool through the controller area network (CAN), circuits 1908 (WH) and 1909 (BK). Check circuits 1908 (WH) and 1909 (BK) between the trailer brake controller C2142b and the data link connector (DLC) C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in one of the CAN circuits, damage to the DLC C251, damage to the trailer brake controller C2142b, or a problem in an in-line connector.
Possible Causes
- CAN circuit 1908 (WH) open
- CAN circuit 1909 (BK) open
- trailer brake controller C2142b
- trailer brake controller