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, go to Step 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 .■
Clear the DTC with the HDS. Start the engine, and warm it up to normal operating temperature (the radiator fan comes on). Drive the vehicle in 2nd gear in the M position for more than 5 seconds, then upshift to 4th gear, and drive in 4th gear for more than 5 seconds. Slow down to a stop. Monitor the OBD status for P0843 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail. Does the result indicate a pass?
YES | - | The problem has been corrected.■
NO | - | Return to Step 1 and recheck.■