DTC P1780: Problem in Shift Control System
- Clear the DTC with the HDS.
- Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears, then slow down to a stop.
- Check for Pending or Confirmed DTCs 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 the DTC other than P1780.
NO -Go to step 4.
- Update the A/T software in the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
- Test-drive the vehicle with the shift lever in D, and let the transmission shift through all five gears, then slow down to a stop.
- Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1780 indicated?
YES -If the PCM was updated, substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the PCM was substituted, go to step 1.
NO -If DTC P1780 is not indicated, or if any other Pending or Confirmed DTCs are indicated, go to step 7.
- Monitor the OBD STATUS for P1780 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 (see PCM REPLACEMENT ). If any other Pending or Confirmed DTCs were indicated on step 6, go to the indicated DTC's troubleshooting.
NO -If the HDS indicates FAILED, check for poor connections and loose terminals at the PCM. If the PCM was updated, substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, go to step 5.