DTC P0780: Problem in Shift Control System

NOTE: Record all freeze data and review General Troubleshooting Information (see GENERAL TROUBLESHOOTING INFORMATION ) before you troubleshoot.

Warm up the engine to normal operating temperature (the radiator fan comes on).
Make sure the transmission is filled to the proper level, and check for fluid leaks.
Drain the ATF (see step 3 on ATF Replacement ) through a strainer. Inspect the strainer for metal debris or excessive clutch material.
Does the strainer contain metal debris or excessive clutch material?
1. YES - Replace the transmission.
2. NO - Replace the ATF (see step 5 on ATF Replacement ), then go to step 4.
Clear the DTC with the HAS.
Test-drive the vehicle in the D5 position through all five gears at speeds over 12 mph (20 km/h) for more than 20 seconds, then slow down to a stop.
Retest-drive the vehicle in the D5 position through all five gears at speeds over 12 mph (20 km/h) for more than 20 seconds, then slow down to a stop.
Monitor the OBD status for P0780 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate FAILED?
1. YES - Go to step 8.
2. NO - Intermittent failure, the system is OK at this time. If the tester indicates NOT COMPLETED, return to step 5 and recheck.
Clear the DTC with the HAS.
Run the engine until the engine coolant temperature reaches 176 °F (80 °C).
Test-drive the vehicle in the D5 position through all five gears at speeds over 12 mph (20 km/h) for more than 20 seconds, then slow down to a stop.
Retest-drive the vehicle in the D5 position through all five gears at speeds over 12 mph (20 km/h) for more than 20 seconds, then slow down to a stop.
Monitor the OBD status for P0780 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate FAILED?
1. YES - Repair hydraulic system related with shift valve D, then go to step 13.
2. NO - Intermittent failure, the system is OK at this time. If the tester indicates NOT COMPLETED, return to step 10 and recheck.
Clear the DTC with the HAS.
Test-drive the vehicle in the D5 position through all five gears at speeds over 12 mph (20 km/h) for more than 20 seconds, then slow down to a stop.
Retest-drive the vehicle in the D5 position through all five gears at speeds over 12 mph (20 km/h) for more than 20 seconds, then slow down to a stop.
Monitor the OBD status for P0780 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate PASSED?
1. YES - Troubleshooting is complete.
2. NO - Return to step 5 and recheck.