DTC Troubleshooting: P0780 (45-1)

DTC P0780:  Mechanical Problem in Hydraulic Control System

NOTE:
  • Record all freeze data before you troubleshoot.
  • Keep these replacement solenoid valves on hand:
    • A/T clutch pressure control solenoid valves A, B and C.
    • Shift solenoid valves A, B, C and E.

1.Check the fuel and emissions system problem and A/T system problem is indicated by the DTC.

Is there any of the DTC?


YES - Perform the troubleshooting flowchart for the indicated code(s). Check for DTC P0780 after troubleshooting.n


NO - Go to 2.


2.Turn the ignition switch OFF.

3.Replace the A/T clutch pressure control solenoid valve A.

4.Replace the A/T clutch pressure control solenoid valves B and C.

5.Reset the PCM memory by removing the No. 6 ECU (15A) fuse in the under-hood fuse/relay box for more than 10 seconds.

6.Drive the vehicle for several minutes in 1st, 2nd, 3rd and 4th gears in [D] position, and stop the vehicle. Do not stop the engine

7.Repeat step 6 to test-drive the vehicle five times.

8.Recheck for DTC P0780.

Is DTC P0780 indicated?


YES - Go to 9.


NO - The problem has been corrected.n


9.Turn the ignition switch OFF.

10.Replace the shift solenoid valves A, B, C and E.

11.Reset the PCM memory by removing the No. 6 ECU (15A) fuse in the under-hood fuse/relay box for more than 10 seconds.

12.Drive the vehicle for several minutes in 1st, 2nd, 3rd and 4th gears in [D] position, and stop the vehicle. Do not stop the engine.

13.Repeat step 12 to test-drive the vehicle five times.

14.Recheck for DTC P0780.

Is DTC P0780 indicated?


YES - Go to 15.


NO - The problem has been corrected.n


15.Turn the ignition switch OFF.

16.Remove the transmission, and overhaul transmission hydraulic control system.

17.Install the transmission on the vehicle.

18.Reset the PCM memory by removing the No. 6 ECU (15A) fuse in the under-hood fuse/relay box for more than 10 seconds.

19.Drive the vehicle for several minutes in 1st, 2nd, 3rd and 4th gears in [D] position, and stop the vehicle. Do not stop the engine.

20.Repeat step 19 to test-drive the vehicle five times.

21.Recheck for DTC P0780.

Is DTC P0780 indicated?


YES - Replace the transmission assembly.n


NO - The problem has been corrected.n