VSA System

VSA DTC Troubleshooting: 51-12

DTC 51-12: Motor Drive 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 the 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 36P connector. Refer to intermittent failures troubleshooting. How to Troubleshoot the VSA System


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

6. Check the No. 58 (30 A) fuse in the under-dash fuse/relay box.

Is the fuse blown?
YES - Go to step 7.

NO - Reinstall the checked fuse, then go to step 9.


7. Disconnect the VSA modulator-control unit 36P connector. Service and Repair

8. Check for continuity between VSA modulator-control unit 36P connector terminal No. 13 and body ground.

Is there continuity?
YES - Repair short to body ground in the wire between the No. 58 (30 A) fuse in the under-dash fuse/relay box and the VSA modulator-control unit.

NO - Install a new No. 58 (30 A) fuse in the under-dash fuse/relay box, then go to step 10.






9. Disconnect the VSA modulator-control unit 36P connector. Service and Repair

10. Measure the voltage between VSA modulator-control unit 36P connector terminal No. 13 and body ground.

Is there battery voltage?
YES - Go to step 11.

NO - Repair open in the wire between the No. 58 (30 A) fuse in the under-dash fuse/relay box and the VSA modulator-control unit.






11. Reconnect the VSA modulator-control unit 36P connector.

12. Update the VSA modulator-control unit if it does not have the latest software. Testing and Inspection If the unit already has the latest software, substitute a known-good VSA modulator-control unit. Service and Repair

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

14. Check for DTCs with the HDS.

Is DTC 51-12 indicated?
YES - Check for loose terminals in the VSA modulator-control unit 36P connector. If the VSA modulator-control unit was updated, substitute a known-good VSA modulator-control unit, Service and Repair then retest. If the VSA modulator-control unit was substituted, go to step 1.

NO - If the VSA modulator-control unit was updated, troubleshooting is complete. If the VSA modulator-control unit was substituted, replace the original VSA modulator-control unit. Service and Repair If any other DTCs are indicated, go to the indicated DTCs troubleshooting.