B1906

DTC Troubleshooting: B1906

DTC B1906:

Immobilizer 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 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.

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. From the BODY ELECTRICAL SYSTEM SELECT menu, select B-CAN CONTROL UNITS INFORMATION, and then select CHECK CONNECTED CONTROL UNITS.

Is the gauge control module detected?

YES -

Go to step 9.

NO -

Go to step 6.

6. Measure the voltage between body ground and gauge control module 32P connector terminals No. 15 and No. 16 individually.





Is there battery voltage?

YES -

Go to step 8.

NO -

Go to step 7.

7. Check the No. 22 (7.5 A) fuse and No. 1 (15 A) fuse in the under-dash fuse/relay box.

Are the fuses OK?

YES -

Repair an open or high resistance in the No. 22 (7.5 A) and/or No. 1 (15 A) fuse circuit.

NO -

Replace the fuse(s). If the fuse blows again, repair a short to ground in the No. 22 (7.5 A) and/or No. 1 (15 A) fuse circuit.

8. Measure the voltage between body ground and gauge control module 32P connector terminals No. 1 and No. 5 individually.





Is there less than 0.2 V?

YES -

Go to step 9.

NO -

Repair an open or high resistance in the ground wire or poor ground (G501).

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

10. Disconnect the immobilizer-keyless control unit 7P connector.

11. Disconnect the gauge control module 32P connector.

12. Check for continuity between immobilizer-keyless control unit 7P connector terminal No. 4 and gauge control module 32P connector terminal No. 17 respectively.





Is there continuity?

YES -

Replace the gauge control module Service and Repair.

NO -

Repair an open or poor connection in the B-CAN wire between the immobilizer-keyless control unit and the gauge control module.