DTC Troubleshooting

DTC Troubleshooting: P0847

DTC P0847: Transmission Fluid Pressure Switch B (3rd Clutch) (Short or 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 3rd Pressure Switch signal with the HDS in the A/T Data List when not in 3rd gear.

Is the 3rd 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 the sequential SportShift mode in S for at least 2 seconds, then slow down to a stop.

5. Monitor the OBD STATUS for P0847 in the DTCs MENU with the HDS.

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

NO - Intermittent failure, the system is OK at this time. Check the OP3SW wire for an intermittent short between the transmission fluid pressure switch B (3rd clutch) and the PCM. If the HDS indicates NOT COMPLETED, return to step 4 and recheck.


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

7. Disconnect the transmission fluid pressure switch B (3rd clutch) connector.

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

9. Check the 3rd Pressure Switch signal with the HDS in the A/T Data List.

Is the 3rd Pressure Switch OFF?
YES - Replace the transmission fluid pressure switch B (3rd clutch), Transmission Fluid Pressure Switch B (3rd Clutch) 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 (22P).

13. Check for continuity between PCM connector terminal C9 and body ground.

Is there continuity?
YES - Repair a short in the wire between PCM connector terminal C9 and the transmission fluid pressure switch B (3rd clutch), 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. Reading and Clearing Diagnostic Trouble Codes

16. Test-drive the vehicle in 3rd gear in the sequential SportShift mode in S for at least 2 seconds, then upshift to 4th gear, and drive in 4th gear for at least 2 seconds. Slow down and stop the wheels.

17. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0847 indicated?
YES - If the PCM was updated, substitute a known-good PCM, Reading and Clearing Diagnostic Trouble Codes then recheck. If the PCM was substituted, go to step 1.

NO - Go to step 18.


18. Monitor the OBD STATUS for P0847 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 on step 17, go to the indicated DTC's troubleshooting.

NO - Check for poor connections and loose terminals at the transmission fluid pressure switch B (3rd clutch) and the PCM. If the PCM was updated, substitute a known-good PCM, Reading and Clearing Diagnostic Trouble Codes then recheck. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, return to step 16 and recheck.


19. Clear the DTC with the HDS.

20. Test-drive the vehicle in 3rd gear in the sequential SportShift mode in S for at least 2 seconds, then upshift to 4th gear, and drive in 4th gear for at least 2 seconds. Slow down and stop the wheels.

21. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0847 indicated?
YES - Check for poor connections and loose terminals at the transmission fluid pressure switch B (3rd clutch) and the PCM, then go to step 1.

NO - Go to step 22.


22. Monitor the OBD STATUS for P0847 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 on step 21, go to the indicated DTC's troubleshooting.

NO - Check for poor connections and loose terminals at the transmission fluid pressure switch B (3rd clutch) and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, return to step 20 and recheck.