B1184

DTC Troubleshooting: B1184

DTC B1184:

Gauge Control Module Lost Communication With AHB Servo Unit (RBS Message)

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. Check for DTCs with the HDS.

Is DTC B1184 indicated?

YES -

Go to step 4.

NO -

Intermittent failure. The gauge control module (tach) is OK at this time. Check for loose or poor connections.�

4. Check for DTCs with the HDS.

Are DTCs B1168, B1169, B1178, B1183, B1184, B1185, and B1187 all indicated at the same time?

YES -

Troubleshoot DTC B1178 B1178.�

NO -

Go to step 5.

5. Check for IMA brake system DTCs with the HDS Initial Inspection and Diagnostic Overview.

Are 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 the gauge control module (tach) 36P connector.

8. Disconnect the servo unit 25P connector.

9. Check for continuity between gauge control module (tach) 36P connector terminals No. 1 and No. 19 and servo unit 25P connector terminals No. 1 and No. 17 respectively.





Is there continuity?

YES -

Substitute a known-good servo unit, and recheck. If the indication goes away, replace the original servo unit Service and Repair. If the DTC is still present, replace the gauge control module (tach) Gauge Control Module Replacement.�

NO -

Repair an open in the wire.�