B1178

DTC Troubleshooting: B1168, B1169, B1178

DTC B1168:

Gauge Control Module Lost Communication With PCM (ENG Message)

DTC B1169:

Gauge Control Module Lost Communication With PCM (A/T Message)

DTC B1178:

F-CAN Communication Circuit Error

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

1. Clear the DTCs with the HDS.

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

3. Wait for at least 6 seconds.

4. Check for DTCs with the HDS.

Are DTCs B1168, B1169, and/or B1178 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time. Check for loose or poor connection between the gauge control module and PCM.�

5. Check for Fuel and Emissions Systems DTCs with the HDS.

Are there any DTCs indicated?

YES -

Go to the indicated DTCs troubleshooting, then recheck.�

NO -

Go to step 6.

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

7. Disconnect gauge control module connector B (28P).

8. Short the SCS line with the HDS.

9. Disconnect PCM connector A (49P).

10. Check for continuity between gauge control module connector B (28P) terminals No. 15 and No. 16 and PCM connector A (49P) terminals A49 and A48 individually.





Is there continuity?

YES -

Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, and recheck. If the indication goes away, replace the original PCM Service and Repair. If the DTC is still present, replace the gauge control module Service and Repair.�

NO -

Repair an open in the wire.�