Transmission
DTC P0843: Open in 2nd Clutch Transmission Fluid Pressure Switch Circuit, or 2nd Clutch Transmission Fluid Pressure Switch Stuck OFFNOTE:
^ Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.
^ This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
^ Information marked with an asterisk (*) applies to the 7-position transmission.
^ Information marked with a double asterisk (**) applies to the 5-position transmission.
1. Clear the DTC with the HDS.
2. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
3. Shift the shift lever into the 2 position* (the S position and select 2nd gear**).
4. Check the 2nd PRESSURE SWITCH signal with the HDS in the A/T data list.
Is the 2nd PRESSURE SWITCH ON?
YES - Go to step 5.
NO - Go to step 7.
5. Drive the vehicle in the 2 position* (2nd gear in the S position**) for more than 5 seconds, then shift to the D position, and drive in 3rd gear for more than 5 seconds. Slow down and stop the wheels.
6. Monitor the OBD status for P0843 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate FAILED?
YES - Go to step 7.
NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the 2nd clutch transmission fluid pressure switch and the PCM. If the HDS indicates NOT COMPLETED, return to step 5 and recheck.
7. Turn the ignition switch OFF.
8. Disconnect the 2nd clutch transmission fluid pressure switch connector.
9. Turn the ignition switch ON (II).
10. Measure the voltage between the 2nd clutch transmission fluid pressure switch connector terminal and body ground.
Is there about 5 V?
YES - Replace the 2nd clutch transmission fluid pressure switch, then go to step 13.
NO - Go to step 11.
11. Turn the ignition switch OFF.
12. Measure voltage between PCM connector terminal C13 and body ground.
Is there about 5 V?
YES - Go to step 17.
NO - Repair open in the wire between PCM connector terminal C13 and the 2nd clutch transmission fluid pressure switch, then go to step 13.
13. Clear the DTC with the HDS.
14. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
15. Drive the vehicle in the 2 position* (2nd gear in the S position**) for more than 5 seconds, then shift to the D position, and drive in 3rd gear for more than 5 seconds. Slow down and stop the wheels.
16. Monitor the OBD status for P0843 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate PASSED?
YES - Troubleshooting is complete.
NO - Check for poor connections or loose terminals at the 2nd clutch transmission fluid pressure switch and the PCM, then go to step 1.
17. Update the PCM if it does not have latest software, or substitute a known-good PCM.
18. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
19. Drive the vehicle in the 2 position* (2nd gear in the S position**) for more than 5 seconds, then shift to the D position, and drive in 3rd gear for more than 5 seconds. Slow down and stop the wheels.
20. Monitor the OBD status for P0843 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM.
NO - If the PCM was updated and screen indicates FAILED, substitute a known-good PCM, then go to step 18. If the PCM was substituted, check for poor connections or loose terminals at the 2nd clutch transmission fluid pressure switch and the PCM, then go to step 1 and recheck. If the screen indicates NOT COMPLETED, go to step 18.