VSA System

VSA DTC Troubleshooting: 51-12

DTC 51-12:

Motor Lock Circuit Malfunction

1. Turn the ignition switch to ON (II).

2. Clear the DTC with the HDS.

3. Turn the ignition switch to LOCK (0), then turn it to ON (II) again.

4. Check for DTCs with the HDS.

Is DTC 51-12 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time. Check for loose terminals at the VSA modulator-control unit 37P connector. Refer to intermittent failures troubleshooting.�

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

6. Check the No. 3 (30 A) fuse in the under-hood fuse/relay box.

Is the fuse blown?

YES -

Go to step 7.

NO -

Reinstall the checked fuse, then go to step 14.

7. Disconnect the VSA modulator-control unit 37P connector.

8. Check for continuity between VSA modulator-control unit 37P connector terminal No. 14 and body ground.





Is there continuity?

YES -

Repair a short to body ground in the wire between the No. 3 (30 A) fuse in the under-hood fuse/relay box and the VSA modulator-control unit.�

NO -

Install a new No. 3 (30 A) fuse in the under-hood fuse/relay box, then go to step 9.

9. Reconnect the VSA modulator-control unit 37P connector.

10. Turn the ignition switch to ON (II).

11. Clear the DTC with the HDS.

12. Turn the ignition switch to LOCK (0), then turn it to ON (II) again.

13. Check for DTCs with the HDS.

Is DTC 51-12 indicated?

YES -

Replace the VSA modulator-control unit Service and Repair.�

NO -

Troubleshooting is complete.�

14. Disconnect the VSA modulator-control unit 37P connector.

15. Measure the voltage between VSA modulator-control unit 37P connector terminal No. 14 and body ground.





Is there battery voltage?

YES -

Check for loose terminals in the VSA modulator-control unit 37P connector. If necessary, substitute a known-good VSA modulator-control unit Service and Repair, and retest.�

NO -

Repair an open in the wire between the No. 3 (30 A) fuse in the under-hood fuse/relay box and the VSA modulator-control unit.�