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DTC P2138

DTC P2138 APP sensor NO. 1/NO. 2 voltage correlation problem
DETECTION CONDITION 
  • The PCM compares the input voltage from APP sensor NO. 1 with the input voltage from APP sensor NO. 2 when the engine is running. If the difference is more than the specification, the PCM determines that there is a APP sensor NO. 1/NO. 2 voltage correlation problem.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition in the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • APP sensor connector or terminals malfunction
  • PCM connector or terminals malfunction
  • APP sensor NO. 1 malfunction
  • APP sensor NO. 2 malfunction
  • PCM malfunction
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA (Mode 12) been recorded?
Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 INSPECT APP SENSOR CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the APP sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
Yes Repair or replace the connector and/or terminals, then go to Step 6.
No Go to the next step.
4 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
Yes Repair or replace the connector and/or terminals, then go to Step 6.
No Go to the next step.
5 INSPECT APP SENSOR 
Yes Replace the accelerator pedal, then go to the next step.
(See ACCELERATOR PEDAL REMOVAL/INSTALLATION ).
No Go to the next step.
6 VERIFY TROUBLESHOOTING OF DTC P2138 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the KOEO or KOER self test.

    (See KOEO/KOER SELF TEST ).

  • Is the same DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
7 VERIFY AFTER REPAIR PROCEDURE 
Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.