DTC Troubleshooting: P0843 (25-4)

DTC P0843:  Open in 2nd Clutch Transmission Fluid Pressure Switch Circuit, or 2nd Clutch Transmission Fluid Pressure Switch Stuck OFF

NOTE:

1.Clear the DTC with the HDS.

2.Start the engine, and warm it up to normal operating temperature (the radiator fan comes on). Shift into the 2 position while pressing the brake pedal, and verify that the SHIFT MAP NUMBER indicates 2nd with the HDS in the A/T data list.

3.Check the 2nd PRES SWITCH signal with the HDS in the A/T data list.

Is the 2nd PRES SWITCH ON?


YES - Go to 4.


NO - Go to 6.


4.Drive the vehicle in 2nd gear in the 2 position for more than 5 seconds, then shift to the D position, and drive in 4th gear for more than 5 seconds. Slow down to a stop.

5.Check the OBD status in DTC Monitor Tool from DTCs/Freeze Data in A/T Mode Menu for a pass/fail test of code P0843.

Did the result indicate a fail?


YES - Go to 6.


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 PCM. If the tester indicates NOT COMPLETE, return to 4 and recheck.n

6.Turn the ignition switch OFF.

7.Disconnect the 2nd clutch transmission fluid pressure switch connector.

8.Turn the ignition switch ON (II).

9.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 11.


NO - Go to 10.

10.Measure the voltage between PCM connector terminal C13 and body ground.

 

Is there about 5 V?


YES - Repair open in the wire between PCM connector terminal C13 and the 2nd clutch transmission fluid pressure switch, then go to 11.


NO - Check for loose or poor connections at PCM connector terminal C13. 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.n


11.Clear the DTC with the HDS.

12.Start the engine, and warm it up to normal operating temperature (the radiator fan comes on). Drive the vehicle in 2nd gear in the 2 position for more than 5 seconds, then shift to the D position, and drive in 4th gear for more than 5 seconds. Slow down to a stop.

13.Check the OBD status in DTC Monitor Tool from DTCs/Freeze Data in A/T Mode Menu for a pass/fail test of code P0843.

Did the result indicate a pass?


YES - The problem has been corrected.n


NO - Return to 1 and recheck.n