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DTC P2138

DTC P2138  : APP Sensor A/B (TP Sensor D/E) Incorrect Voltage Correlation

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P2138 APP Sensor A/B (TP Sensor D/E) Incorrect Voltage Correlation    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Turn the vehicle to the OFF (LOCK) mode.

    -4. Turn the vehicle to the ON mode.

    -5. Press the accelerator pedal to the floor.

    -6. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC
    P2138 APP Sensor A/B (TP Sensor D/E) Incorrect Voltage Correlation    

    DTC (PGM-FI)

    Is DTC P2138 indicated?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the APP sensor and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

  2. Determine possible failure area (APP sensor, others)

    -1. Check the parameter(s) below with the HDS.

    Signal Current conditions
    Values Unit
    APP Sensor A Voltage    
    APP Sensor B Voltage    

    Data List

    Are they the same voltage?

    YES 

    Go to step 3.

    NO 

    Replace the accelerator pedal module .

  3. Determine possible failure area (PCM, others)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    -3. Disconnect the following connector.

    PCM connector A (50P)

    -4. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
    Test point 1 PCM connector A (50P) No. 32
    Test point 2 PCM connector A (50P) No. 34

    Is there continuity?

    YES 

    Go to step 4.

    NO 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC P2138 goes away and the PCM was substituted, replace the original PCM .

  4. Shorted wire check (APS1 line to APS2 line)

    -1. Disconnect the following connector.

    APP sensor 6P connector

    -2. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector A (50P): disconnected
      APP sensor 6P connector: disconnected
    Test point 1 PCM connector A (50P) No. 32
    Test point 2 PCM connector A (50P) No. 34

    Is there continuity?

    YES 

    Repair a short in the APS1 wire to the APS2 wire between the PCM connector terminals A32 (APS1 line) and A34 (APS2 line).

    NO 

    The APS1 wire and the APS2 wire are OK. Replace the accelerator pedal module .