DTC Troubleshooting

DTC Troubleshooting: P0812

DTC P0812: Transmission Range Switch ATP R Switch (Open)

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information. How To Troubleshoot A/T Systems

- 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 to ON (II).

2. Shift to R, 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 to LOCK (0).

4. Disconnect the transmission range switch connector.

5. Check for continuity between transmission range switch connector terminal No. 6 and body ground.

Is there continuity?
YES - Go to step 6.

NO - Repair an open in the wire between transmission range switch connector terminal No. 6 and ground (G101, G102), or repair poor ground (G101, G102), then go to step 14.






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

7. Measure the voltage between transmission range switch connector terminals No. 6 and No. 8.

Is there voltage?
YES - Go to step 8.

NO - Repair an open in the wire between PCM connector terminal D16 and the transmission range switch, then go to step 14.






8. Check for continuity between transmission range switch connector terminals No. 6 and No. 8 while the shift lever is in R, and when the shift lever is shifted to any position other than R.

Is there continuity while the shift lever is in R, and no continuity when the shift lever is shifted to any position other than R?
YES - Check for poor connections and loose terminals at the transmission range switch and the PCM. If the connections are OK, go to step 9.

NO - Replace the transmission range switch, Service and Repair then go to step 14.






9. Connect the transmission range switch connector.

10. Update the A/T software in the PCM if it does not have the latest software, PCM Update or substitute a known-good PCM. Reading and Clearing Diagnostic Trouble Codes

11. Test-drive the vehicle in R at speeds below 3 mph (5 km/h) for at least 2 seconds, then increase the speed and test-drive at speeds over 3 mph (5 km/h) for at least 2 seconds. Slow down and stop the wheels.

12. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0812 indicated?
YES - If the PCM was updated, substitute a known-good PCM, Reading and Clearing Diagnostic Trouble Codes then recheck. If the PCM was substituted, go to step 1.

NO - Go to step 13.


13. Monitor the OBD STATUS for P0812 in the DTCs MENU with the HDS.

Does the HDS indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. Service and Repair If any other Pending or Confirmed DTCs were indicated on step 12, go to the indicated DTC's troubleshooting.

NO - Check for poor connections and loose terminals at the transmission range switch and the PCM. If the PCM was updated, substitute a known-good PCM, Reading and Clearing Diagnostic Trouble Codes then recheck. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, return to step 11 and recheck.


14. Connect the transmission range switch connector.

15. Clear the DTC with the HDS.

16. Test-drive the vehicle in R at speeds below 3 mph (5 km/h) for at least 2 seconds, then increase the speed and test-drive at speeds over 3 mph (5 km/h) for at least 2 seconds. Slow down and stop the wheels.

17. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0812 indicated?
YES - Check for poor connections and loose terminals at the transmission range switch and the PCM, then 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 HDS indicate PASSED?
YES - Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated on step 17, go to the indicated DTC's troubleshooting.

NO - Check for poor connections and loose terminals at the transmission range switch and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, return to step 16 and recheck.