DTC Troubleshooting
DTC Troubleshooting: P0848 (26)
DTC P0848:
Open in Transmission Fluid Pressure Switch B (3rd Clutch) Circuit, or Transmission Fluid Pressure Switch B (3rd Clutch) Stuck OFF
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information How to Troubleshoot the A/T System.
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
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 with the shift lever in D, and check if the Shift Control indicates 3 with the HDS in the A/T Data List.
5. Check the 3rd Pressure Switch with the HDS in the A/T Data List.
Is the 3rd Pressure Switch ON?
YES -
Go to step 6.
NO -
Go to step 8.
6. Test-drive the vehicle in 3rd gear with the shift lever in D for at least 2 seconds.
7. Monitor the OBD STATUS for P0848 in the DTCs MENU with the HDS.
Does the HDS indicate FAILED?
YES -
Go to step 8.
NO -
If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals between transmission fluid pressure switch B (3rd clutch) and the PCM. If the HDS indicates NOT COMPLETED, go to step 6.
8. Turn the ignition switch to LOCK (0).
9. Disconnect the transmission fluid pressure switch B (3rd clutch) connector.
10. Connect a jumper wire between the transmission fluid pressure switch B (3rd clutch) connector terminal and body ground.
11. Turn the ignition switch to ON (II).
12. Check the 3rd Pressure Switch with the HDS in the A/T Data List.
Is the 3rd Pressure Switch ON?
YES -
Go to step 13.
NO -
Go to step 16.
13. Reconnect the transmission fluid pressure switch B (3rd clutch) connector.
14. Clear the DTC with the HDS.
15. Measure the 3rd clutch pressure A/T Pressure Test.
Is the 3rd clutch pressure within the service limit?
YES -
Replace transmission fluid pressure switch B (3rd clutch) Transmission Fluid Pressure Switch B (3rd Clutch) Replacement, then go to step 21.
NO -
Repair shift valves A, B, and C, and the related hydraulic circuit, or replace the transmission, then go to step 24.
16. Remove the jumper wire, then measure the voltage between the transmission fluid pressure switch B (3rd clutch) connector terminal and body ground.
Is there about 5 V?
YES -
Replace transmission fluid pressure switch B (3rd clutch) Transmission Fluid Pressure Switch B (3rd Clutch) Replacement, then go to step 21.
NO -
Go to step 17.
17. Turn the ignition switch to LOCK (0).
18. Jump the SCS line with the HDS.
19. Disconnect PCM connector B (49P).
20. Check for continuity between PCM connector terminal B9 and the transmission fluid pressure switch B (3rd clutch) connector terminal.
Is there continuity?
YES -
Go to step 28.
NO -
Repair an open in the wire between PCM connector terminal B9 and the transmission fluid pressure switch B (3rd clutch) connector terminal, then go to step 21.
21. Reconnect all connectors.
22. Turn the ignition switch to ON (II).
23. Clear the DTC with the HDS.
24. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
25. Test-drive the vehicle in 3rd 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 P0848 indicated?
YES -
Check for poor connections or loose terminals between transmission fluid pressure switch B (3rd clutch) and the PCM, then go to step 1.
NO -
Go to step 27.
27. Monitor the OBD STATUS for P0848 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 26, go to the indicated DTC's troubleshooting.
NO -
If the HDS indicates FAILED, check for poor connections or loose terminals between transmission fluid pressure switch B (3rd clutch) and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, go to step 24.
28. Reconnect all connectors.
29. Update the PCM if it does not have the latest software ECM/PCM Update (M/T), or substitute a known-good PCM.
30. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
31. Test-drive the vehicle in 3rd gear with the shift lever in D for at least 2 seconds, then drive in 4th gear for at least 2 seconds.
32. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0848 indicated?
YES -
Check for poor connections or loose terminals between transmission fluid pressure switch B (3rd clutch) and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 30. If the PCM was substituted, go to step 1.
NO -
Go to step 33.
33. Monitor the OBD STATUS for P0848 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 32, go to the indicated DTC's troubleshooting.
NO -
If the HDS indicates FAILED, check for poor connections or loose terminals between transmission fluid pressure switch B (3rd clutch) and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 30. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, go to step 30.