DTC P0780: Shift Control System

NOTE:

Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information (see GENERAL TROUBLESHOOTING INFORMATION ).
This code is stored whenever DTCs P1730, P1731, P1732, P1733, and P1734 are detected.

Check for other Pending or Confirmed DTCs indicated simultaneous with DTC P0780.
NOTE: DTC P0780 means there is one or more A/T DTCs about the shift control system.

Are there other DTCs?

YES -Troubleshoot indicated DTC(s):
- P1730 (see DTC P1730: PROBLEM IN SHIFT CONTROL SYSTEM )
- P1731 (see DTC P1731: PROBLEM IN SHIFT CONTROL SYSTEM )
- P1732 (see DTC P1732: PROBLEM IN SHIFT CONTROL SYSTEM )
- P1733 (see DTC P1733: PROBLEM IN SHIFT CONTROL SYSTEM )
- P1734 (see DTC P1734: PROBLEM IN SHIFT CONTROL SYSTEM )
NO -Go to step 2.
Update the A/T software in the PCM if it does not have the latest software; K24Z1 engine (see PCM UPDATE ), K24Z6 engine (see PCM UPDATE ), or substitute a known-good PCM; K24Z1 engine (see SUBSTITUTING THE PCM ), K24Z6 engine (see SUBSTITUTING THE PCM ).
Test-drive the vehicle for several minutes 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 P0780 indicated?

YES -If the PCM was updated, substitute a known-good PCM; K24Z1 engine (see SUBSTITUTING THE PCM ), K24Z6 engine (see SUBSTITUTING THE PCM ), then recheck. If the PCM was substituted, reinstall the original PCM, then Go to step 1.

NO -Go to step 5.
Monitor the OBD STATUS for P0780 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; K24Z1 engine (see PCM REPLACEMENT ), K24Z6 engine (see PCM REPLACEMENT ). If any other Pending or Confirmed DTCs were indicated on step 4, go to the indicated DTC's troubleshooting.

NO -If the HDS indicates FAILED, check for poor connections and loose terminals at shift solenoid valves, A/T clutch pressure control solenoid valves, and the PCM. If the PCM was updated, substitute a known-good PCM; K24Z1 engine (see SUBSTITUTING THE PCM ), K24Z6 engine (see SUBSTITUTING THE PCM ), then recheck. If the PCM was substituted, reinstall the original PCM, then Go to step 1. If the HDS indicates NOT COMPLETED, Go to step 3 and recheck.