DTC Troubleshooting
DTC P0812: Open in Transmission Range Switch ATP R Switch CircuitNOTE:
- Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.
- This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
1. Turn the ignition switch ON (II).
2. Shift the shift lever into the R position, and verify the A/T R SWITCH signal with the HDS in the A/T data list.
Is the A/T R SWITCH ON?
YES - Intermittent failure, the system is OK at this time.
NO - Go to step 3.
3. Turn the ignition switch OFF.
4. Disconnect the transmission range switch connector.
5. Check for continuity between transmission range switch connector terminal No. 5 and body ground.
Is there continuity?
YES - Go to step 6.
NO - Repair an open in the wire between the transmission range switch and ground (G101, G102), or repair a poor ground (G101, G102), then go to step 9.
6. Turn the ignition switch ON (II).
7. Measure voltage between transmission range switch connector terminals No. 3 and No. 5.
Is there voltage?
YES - Go to step 9.
NO - Repair an open in the wire between the transmission range switch and PCM connector terminal D16, then go to step 9.
8. Check for continuity between the No. 3 and No. 5 terminals at the transmission range switch.
Is there continuity when the shift lever is in the R position, and no continuity when the shift lever is in any position other than R?
YES - Go to step 15.
NO - Replace the transmission range switch, then go to step 9.
9. Reconnect all connectors.
10. Turn the ignition switch ON (II).
11. Clear the DTC with the HDS.
12. Test-drive the vehicle in the R position at speeds below 3 mph (5 km/h) for more than 2 seconds, then increase the speed and test-drive at speeds over 3 mph (5 km/h) for more than 2 seconds. Slow down and stop the wheels.
13. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0812 indicated?
YES - Check for poor connections or loose terminals at the transmission range switch and the PCM, then go to step 1.
NO - Go to step 14.
14. Monitor the OBD STATUS for P0812 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete.
NO - Return to step 3 and recheck.
15. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
16. Test-drive the vehicle in the R position at speeds below 3 mph (5 km/h) for more than 2 seconds, then increase the speed and test-drive at speeds over 3 mph (5 km/h) for more than 2 seconds. Slow down and stop the wheels.
17. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0812 indicated?
YES - Check for poor connections or loose terminals at the transmission range switch and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 18. If the PCM was substituted, go to step 1.
NO - Go to step 18.
18. Monitor the OBD STATUS for P0812 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete.
NO - Return to step 3 and recheck.