P0873
DTC P0873: Open in 4th Clutch Transmission Fluid Pressure Switch Circuit, or 4th Clutch Transmission Fluid Pressure Switch Stuck OFFNOTE: Record all freeze data and review General Troubleshooting Information before you troubleshoot. 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. Drive the vehicle in 4th gear in the M position for more than 5 seconds. Slow down and stop the wheels.
4. Check the 4th PRES SWITCH signal with the HDS in the A/T data list.
Is the 4th PRES SWITCH ON?
YES - Go to step 5.
NO - Go to step 7.
5. Drive the vehicle in 4th gear in the M position for more than 5 seconds. Slow down and stop the wheels.
6. Monitor the OBD status for P0873 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 4th clutch transmission fluid pressure switch and the PCM. If the tester indicates NOT COMPLETED, return to step 5 and recheck.
7. Turn the ignition switch OFF.
8. Disconnect the 4th clutch transmission fluid pressure switch connector.
9. Turn the ignition switch ON (II).
10. Measure the voltage between the 4th clutch transmission fluid pressure switch connector terminal and body ground.
Is there about 5 V?
YES - Replace the 4th clutch transmission fluid pressure switch, then go to step 12.
NO - Go to step 11.
11. Measure the voltage between PCM connector terminal C20 and body ground.
Is there about 5 V?
YES - Repair an open in the wire between PCM connector terminal C20 and the 4th clutch transmission fluid pressure switch, then go to step 12.
NO - Check for loose or poor connections at PCM connector terminal C9. If the connection is OK, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
12. Clear the DTC with the HDS.
13. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on).
14. Drive the vehicle in 4th gear in the M position for more than 5 seconds. Slow down and stop the wheels.
15. Monitor the OBD status for P0873 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate PASSED?
YES - Troubleshooting is complete.
NO - Return to step 7 and recheck.