DTC Troubleshooting

DTC P1780: Problem in Shift Control System

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Test-drive the vehicle for several minutes in the D position through all five gears, then slow down to a stop.
4. Repeat the test-drive in step 3.
5. Check for other DTCs indicated simultaneous with the HDS.

NOTE: DTC P1780 means there is one or more A/T DTCs about the shift control system.

Are there other DTCs?
YES - Troubleshoot a problem as indicated by the DTC.
NO - Go to step 6.

6. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
7. Test-drive the vehicle for several minutes in the D position through all five gears.
8. Repeat the test-drive in step 7.
9. Check for DTCs with the HDS.
Is DTC P1780 indicated?
YES - If the PCM was updated, substitute a known-good PCM, then go to step 7. If the PCM was substituted, go to step 1.
NO - Go to step 10.

10. Monitor the OBD STATUS for P1780 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other DTCs were indicated in step 9, go to the indicated DTC's troubleshooting.
NO - If the screen indicates FAILED, check for poor connections or loose terminals at the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 7. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 7.