DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P1780

DTC P1780 : Shift Control System (Transmission Default Mode)

NOTE:
* Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information How To Troubleshoot The A/T System.
* This code is stored whenever DTCs P1746 and P1747 are detected.

1. DTC check:

DTC check
-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears.

-4. Check for other Pending or Confirmed DTCs indicated along with DTC P1780 with the HDS.
NOTE: DTC P1780 means there is one or more A/T DTCs regarding the shift control system.

Are there other DTCs?
-YES- Go to the indicated DTC's troubleshooting.
-NO- There are no DTCs along with DTC P1780. Update the PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good PCM , then do the repair verification.

Repair verification (OBD STATUS check):

-1. Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears.

-2. Monitor the OBD STATUS for P1780 in the DTCs MENU with the HDS.

Does the HDS indicate PASSED, FAILED, or NOT COMPLETED?
-PASSED- Troubleshooting is complete. If the PCM was substituted, replace the original PCM . Check for other DTC after this troubleshooting. If any other Pending or Confirmed DTCs were indicated, go to the indicated DTC's troubleshooting.
-FAILED- Go to step 1 and recheck. If the PCM was updated, substitute a known-good PCM , and check the OBD STATUS again.
-NOT COMPLETED- Meet the test condition, and check the OBD STATUS again.