DTC Troubleshooting
DTC Troubleshooting: P0842 (25)
DTC P0842:
Short in Transmission Fluid Pressure Switch A (2nd Clutch) Circuit, or Transmission Fluid Pressure Switch A (2nd Clutch) Stuck ON
NOTE:
- Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information Reading and Clearing Diagnostic Trouble Codes.
- This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Check the 2nd Pressure Switch in the A/T Data List with the HDS when not in 2nd gear.
Is the 2nd Pressure Switch OFF?
YES -
Go to step 4.
NO -
Go to step 7.
4. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
5. Test-drive the vehicle in 4th gear with the shift lever in D for at least 2 seconds.
6. Monitor the OBD STATUS for P0842 in the DTCs MENU with the HDS.
Does the HDS indicate FAILED?
YES -
Go to step 7.
NO -
If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check for an intermittent short to body ground in the wire between transmission fluid pressure switch A (2nd clutch) and the PCM. If the HDS indicates NOT COMPLETED, go to step 4.
7. Turn the ignition switch to LOCK (0).
8. Disconnect the transmission fluid pressure switch A (2nd clutch) connector.
9. Turn the ignition switch to ON (II).
10. Check the 2nd Pressure Switch in the A/T Data List with the HDS.
Is the 2nd Pressure Switch OFF?
YES -
Replace transmission fluid pressure switch A (2nd clutch) Transmission Fluid Pressure Switch A (2nd Clutch) Replacement, then go to step 15.
NO -
Go to step 11.
11. Turn the ignition switch to LOCK (0).
12. Jump the SCS line with the HDS.
13. Disconnect PCM connector B (49P).
14. Check for continuity between PCM connector terminal B8 and body ground.
Is there continuity?
YES -
Repair a short to body ground in the wire between PCM connector terminal B8 and transmission fluid pressure switch A (2nd clutch), then go to step 15.
NO -
Go to step 22.
15. Reconnect all connectors.
16. Turn the ignition switch to ON (II).
17. Clear the DTC with the HDS.
18. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
19. Test-drive the vehicle in 2nd gear with the shift lever in D for at least 2 seconds, then drive in 4th gear for at least 2 seconds.
20. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0842 indicated?
YES -
Check for an intermittent short to body ground in the wire between transmission fluid pressure switch A (2nd clutch) and the PCM, then go to step 1.
NO -
Go to step 21.
21. Monitor the OBD STATUS for P0842 in the DTCs MENU with the HDS.
Does the HDS indicate PASSED?
YES -
Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 20, go to the indicated DTC's troubleshooting.�
NO -
If the HDS indicates FAILED, check for an intermittent short to body ground in the wire between transmission fluid pressure switch A (2nd clutch) and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, go to step 18.
22. Reconnect all connectors.
23. Update the PCM if it does not have the latest software ECM/PCM Update (M/T), or substitute a known-good PCM.
24. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
25. Test-drive the vehicle in 2nd gear with the shift lever in D for at least 2 seconds, then drive in 4th gear for at least 2 seconds.
26. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0842 indicated?
YES -
Check for an intermittent short to body ground in the wire between transmission fluid pressure switch A (2nd clutch) and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 24. If the PCM was substituted, go to step 1.
NO -
Go to step 27.
27. Monitor the OBD STATUS for P0842 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 Service and Repair. If any other Pending or Confirmed DTCs were indicated in step 26, go to the indicated DTC's troubleshooting.�
NO -
If the HDS indicates FAILED, check for an intermittent short to body ground in the wire between transmission fluid pressure switch A (2nd clutch) and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 24. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, go to step 24.