B1906

DTC B1906: Immobilizer-Keyless Control Unit Lost Communication with Gauge Control Module (A/T Message)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in 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 ON (II).
3. Wait for 6 seconds or more.
4. Check for DTCs with the HDS.

Is DTC B1906 indicated?

YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections between the gauge control module and the immobilizer-keyless control unit.

5. Select the BODY ELECTRICAL system select menu, then enter the UNIT INFORMATION menu.
6. Check the condition of the gauge control module from the CONNECTED UNIT.

Is NOT AVAILABLE indicated?

YES - Go to step 7.

NO - Replace the gauge control module.

7. Turn the ignition switch to LOCK (0).
8. Disconnect the gauge control module 36P connector.
9. Turn the ignition switch ON (II).
10. Measure the voltage between the gauge control module 36P connector No. 18 and No. 36 terminals and body ground individually.






Is there battery voltage?

YES - Go to step 11.

NO - Check the No. 23 (10 A) fuse in the under-hood fuse/relay box and the No. 10 (7.5 A) fuse in the under-dash fuse/relay box. If the fuse is blown, replace the fuse and recheck the DTCs. If the fuses are OK, repair an open in the wire between the under-dash fuse/relay box and the gauge control module.

11. Turn the ignition switch to LOCK (0).
12. Check for continuity between the gauge control module 36P connector No. 15 and No. 19 terminals and body ground individually.






Is there continuity?

YES - Go to step 13.

NO - Repair an open in the wire or poor ground (G501).

13. Disconnect under-dash fuse/relay box connector Q (16P).
14. Check for continuity between under-dash fuse/relay box connector Q (16P) No. 6 terminal and the gauge control module 36P connector No. 20 terminal.






Is there continuity?

YES - Replace the gauge control module.

NO - Repair an open in the wire between the under-dash fuse/relay box and the gauge control module.