Automatic Transmission

DTC P2123: Accelerator Pedal Position (APP) Sensor A (Throttle Position Sensor D) Circuit High Voltage Input

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.

1. Clear the DTC with the HDS.
2. Turn the ignition switch ON (II).
3. Check whether DTC P2123 is indicated in the DTCs/Freeze Data in PGM-FI Mode Menu with the HDS.

Is DTC P2123 indicated in the PGM-FI system?

YES - Troubleshoot for DTC P2123 in the PGM-FI System.

NO - Go to step 4.

4. Check whether DTC P2123 is indicated in the DTCs/Freeze Data in A/T Mode Menu with the HDS.

Is DTC P2123 indicated?

YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time.

5. Update the A/T software in the PCM if it does not have the latest software, or substitute a known-good PCM.
6. Turn the ignition switch ON (II).
7. Check for DTC(s) in the DTCs/Freeze Data in A/T Mode Menu with the HDS.

Is DTC P2123 indicated?

YES - If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.

NO - Go to step 8.

8. Monitor the OBD status for P2123 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. If any other DTCs were indicated on step 7, go to the indicated DTC's troubleshooting.

NO - If the HDS indicates FAILED, check for poor connections and loose terminals at accelerator pedal position sensor A and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, return to step 6 and recheck.