B1178

DTC Troubleshooting: B1173, B1178

DTC B1173: Gauge control module lost communication with the TPMS control unit (TPMS message)

DTC B1178: F-CAN Communication Line Error

1. Clear the DTCs with the HDS.

2. Turn the ignition switch to LOCK (0), and then back to ON (II).

3. Wait for 6 seconds or more.

4. Check for DTCs with the HDS.

Are DTCs B1173 or 1178 indicated?
YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the gauge assembly and the TPMS control unit.


5. Check for TPMS DTCs with the HDS.

Is any DTCs indicated?
YES - Go to the indicated DTCs, then recheck.

NO - Go to step 6.


6. Turn the ignition switch to LOCK (0).

7. Disconnect gauge assembly connector A (22P).

8. Disconnect the TPMS control unit 20P connector.

9. Check for continuity between gauge assembly connector A (22P) terminals No. 21 and No. 22 and body ground individually.

Is there continuity?
YES - Repair a short to body ground on the appropriate wire.

NO - Go to step 10.






10. Check for continuity between gauge assembly connector A (22P) terminals No. 21 and No. 22.

Is there continuity?
YES - Repair a short in the wire between gauge assembly A (22P) connector terminals No. 21 (CAN2 L Line) and No. 22 (CAN2 H Line).

NO - Go to step 11.






11. Check for continuity between gauge assembly connector A (22P) terminals No. 21 and No. 22 and the TPMS control unit 20P connector terminals No. 1 and No. 11 respectively.

Is there continuity?
YES - Substitute a known-good TPMS control unit , and recheck. If the indication goes away, replace the original TPMS control unit. If the DTC is still present, replace the gauge assembly. Service and Repair

NO - Repair an open in the wire.