A/T System

DTC Troubleshooting: P2123 (20) (A/T System)

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

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information. How to Troubleshoot A/T Systems

1. Clear the DTC with the HDS.

2. Turn the ignition switch to 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. P2123

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, PCM Update or substitute a known-good PCM. How to Troubleshoot A/T Systems

6. Start the engine, and let it idle for 2 minutes.

7. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2123 indicated?
YES - If the PCM was updated, substitute a known-good PCM, How to Troubleshoot A/T Systems 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 HDS indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. Service and Repair If any other DTCs were indicated on step 7, go to the indicated DTC's troubleshooting.

NO - 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, How to Troubleshoot A/T Systems then recheck. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, return to step 6 and recheck.