DTC Troubleshooting: B1906

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

1.Clear the DTCs with the HDS.

2.Turn the ignition switch OFF, 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 5.

NO - Intermittent failure, the gauge control module (tach) is OK at this time. Check for loose or poor connections at the gauge control module (tach) 36P connector and at the immobilizer-keyless control unit 7P connector.n

5.Turn the ignition switch OFF.

6.Select the BODY ELECTRICAL system select menu, then enter the UNIT INFORMATION menu.

7.Check the condition of the gauge control module (tach) from the CONNECTED UNIT list.

Is NOT AVAILABLE indicated?

YES - Go to 8.

NO - Replace the immobilizer-keyless control unit.n

8.Do the gauge control module (tach) input test.

Are all inputs OK?

YES - Go to 9.

NO - Repair the faulty input, then recheck the DTCs.n

9.Disconnect the under-dash fuse/relay box connector Q (16P).

10.Disconnect the gauge control module (tach) 36P connector.

11.Check for continuity between the under-dash fuse/relay box connector Q (16P) No. 6 terminal and gauge control module (tach) 36P connector No. 21 terminal.


Is there continuity?

YES - Replace the gauge control module (tach).n

NO - Repair an open in the wire between the immobilizer-keyless control unit and the gauge control module (tach).n