P0843
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.
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.
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 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 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 15.
NO - Go to step 11.
11. Turn the ignition switch OFF.
12. Jump the SCS line with the HDS.
13. Disconnect PCM connector B (44P).
14. Check for continuity between PCM connector terminal B8 and 2nd clutch transmission fluid pressure switch connector terminal.
Is there continuity?
YES - Check for loose or poor connections at PCM connector terminal B8. If the connection is OK, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck for DTC P0843. If the symptom/indication goes away with a known-good PCM, replace the original PCM, then to step 15.
NO - Repair open in the wire between PCM connector terminal B8 and the 2nd clutch transmission fluid pressure switch, then go to step 15.
15. Clear the DTC with the HDS.
16. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
17. Drive the vehicle in the 2 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.
18. 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 - If the PCM was updated and the screen indicates FAILED, substitute a known-good PCM, then return to step 15. If the PCM was substituted and the screen indicates FAILED, return to step 1 and recheck. If the screen indicates NOT COMPLETED, return to step 16.