DTC Troubleshooting

DTC Troubleshooting: P0842 (25)

DTC P0842: Short in 2nd Clutch Transmission Fluid Pressure Switch Circuit, or 2nd Clutch Transmission Fluid Pressure Switch Stuck ON

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information. How to Troubleshoot A/T Systems

- This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

1. Clear the DTC with the HDS.

2. Check the 2nd Pressure Switch signal with the HDS in the A/T Data List when not in 2nd gear.

Is the 2nd Pressure Switch OFF?
YES - Go to step 3.

NO - Go to step 6.


3. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).

4. Test-drive the vehicle in 3rd gear in D for at least 2 seconds, then slow down to a stop.

5. Monitor the OBD status for P0842 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.

Does the HDS indicate FAILED?
YES - Go to step 6.

NO - If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check the OP2SW wire for an intermittent short to body ground between the 2nd clutch transmission fluid pressure switch and the PCM. If the HDS indicates NOT COMPLETED, go to step 4.


6. Turn the ignition switch to LOCK (0).

7. Disconnect the 2nd clutch transmission fluid pressure switch connector.

8. Turn the ignition switch to ON (II).

9. Check the 2nd Pressure Switch signal with the HDS in the A/T Data List.

Is the 2nd Pressure Switch OFF?
YES - Replace the 2nd clutch transmission fluid pressure switch, 2nd Clutch Transmission Fluid Pressure Switch Replacement then go to step 19.

NO - Go to step 10.


10. Turn the ignition switch to LOCK (0).

11. Jump the SCS line with the HDS.

12. Disconnect PCM connector C (49P).

13. Check for continuity between PCM connector terminal C27 and body ground.

Is there continuity?
YES - Repair short in the wire between PCM connector terminal C27 and the 2nd clutch transmission fluid pressure switch, then go to step 19.

NO - Go to step 14.






14. Reconnect all connectors.

15. Update the A/T software in the PCM if it does not have the latest software, PCM Update or substitute a known-good PCM. Initial Inspection and Diagnostic Overview

16. Drive the vehicle in 2nd gear in D for at least 2 seconds, then press the accelerator pedal so that the transmission upshifts to 3rd gear, then 4th gear. Drive for at least 2 seconds in each gear. Slow down and stop the wheels.

17. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0842 indicated?
YES - If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then recheck. If the PCM was substituted, go to step 1.

NO - Go to step 18.


18. Monitor the OBD status for P0842 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.

Does the HDS indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. Service and Repair If any other DTCs were indicated on step 17, go to the indicated DTC's troubleshooting.

NO - If the HDS indicates FAILED, check for poor connections and loose terminals between the 2nd clutch transmission fluid pressure switch and the PCM. If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then recheck. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, go to step 16.


19. Reconnect all connectors.

20. Clear the DTC with the HDS.

21. Drive the vehicle in 2nd gear in D for at least 2 seconds, then press the accelerator pedal so that the transmission upshifts to 3rd gear, then 4th gear. Drive for at least 2 seconds in each gear. Slow down and stop the wheels.

22. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0842 indicated?
YES - Check for poor connections and loose terminals between the 2nd clutch transmission fluid pressure switch and the PCM, then go to step 1.

NO - Go to step 23.


23. Monitor the OBD status for P0842 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.

Does the HDS indicate PASSED?
YES - Troubleshooting is complete. If any other DTCs were indicated on step 22, go to the indicated DTC's troubleshooting.

NO - If the HDS indicates FAILED, check for poor connections and loose terminals between the 2nd clutch transmission fluid pressure switch and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, go to step 21.