DTC 51-12
DTC 51-12: Motor Lock Circuit Malfunction1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Turn the ignition switch OFF, then turn it 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 37P connector. Refer to intermittent failures troubleshooting.
5. Turn the ignition switch OFF.
6. Check the No. 17 (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 9.
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 Short to body ground in the wire between the No. 17 (30 A) fuse in the under-hood fuse/relay box and the VSA modulator-control unit.
NO - Install a new No. 17 (30 A) fuse in the underhood fuse/relay box, then Go to step 10.
9. Disconnect the VSA modulator-control unit 37P connector.
10. Measure 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 and retest.
NO - Repair open in the wire between the No. 17 (30 A) fuse in the under-hood fuse/relay box and the VSA modulator-control unit.