SFI SYSTEM, Diagnostic DTC:P2138

DTC Code DTC Name
P2138 Throttle / Pedal Position Sensor / Switch "D" / "E" Voltage Correlation

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P2138 Throttle / Pedal Position Sensor / Switch "D" / "E" Voltage Correlation

DTC Detection Condition


    Enable Criteria

  • None


    Malfunction Criteria

  • Re-scaled sensor voltages do not correlate higher than 8 % difference

  • Raw sensor voltages do not correlate (short circuit). Voltage difference less than 0.025V


    Diagnostic Mask

  • The MIL will be illuminated if a fault is present for 1 trips


    Monitor

  • Continuous


    Potential failure modes

  • PPS1 (D) reading incorrectly

  • PPS2 (E) reading incorrectly

  • Accelerator pedal sensor assembly

  • Accelerator pedal sensor assembly circuit

 Comes on DTC stored

MONITOR DESCRIPTION

Two potentiometers are built into the throttle pedal unit in order to provide a throttle demand signal to the ECU. Two processors within the ECU compare the two output signals, which should match within a defined tolerance. Note that the potentiometers operate on 5 volts.

WIRING DIAGRAM

Refer to DTC P2122.

Click here

CAUTION / NOTICE / HINT

Note

If any DTCs related to the crankshaft position sensor, throttle position sensor, accelerator pedal sensor assembly, manifold absolute pressure sensor and camshaft position sensor are output simultaneously, inspect the VC circuit of each component.

Tech Tips

Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. READ VALUE USING GTS (ACCEL SENSOR OUT)


    1. B0048AUC05
      *a Fully Depressed
      *b Fully Released

      Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine / Data List/ Accel Sensor Out No.1 and Accel Sensor Out No.2.

    5. Read the value displayed on the GTS.

      Standard Voltage
      Accelerator Pedal Operation Accel Sensor Out No.1 Accel Sensor Out No.2 Difference between Accel Sensor Out No.1 and Accel Sensor Out No.2
      Fully Released 0.5 to 1.1 V 1.2 to 2.0 V More than 0.02 V
      Fully Depressed 2.6 to 4.5 V 3.4 to 4.75 V
      Result
      Proceed to
      OK
      NG

    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here

    NG

  2. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL SENSOR ASSEMBLY - ECM)


    1. Disconnect the A36 accelerator pedal sensor assembly connector.

    2. Disconnect the A116 ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A36-6 (VPA) - A116-2 (VPA) Always Below 1 Ω
      A36-5 (EPA) - A116-10 (EPA) Always Below 1 Ω
      A36-4 (VCPA) - A116-18 (VCPA) Always Below 1 Ω
      A36-3 (VPA2) - A116-1 (VPA2) Always Below 1 Ω
      A36-2 (EPA2) - A116-46 (EPA2) Always Below 1 Ω
      A36-1 (VCP2) - A116-45 (VCP2) Always Below 1 Ω
      A36-6 (VPA) or A116-2 (VPA) - Body ground and other terminals Always 10 kΩ or higher
      A36-4 (VCPA) or A116-18 (VCPA) - Body ground and other terminals Always 10 kΩ or higher
      A36-3 (VPA2) or A116-1 (VPA2) - Body ground and other terminals Always 10 kΩ or higher
      A36-1 (VCP2) or A116-45 (VCP2) - Body ground and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ACCELERATOR PEDAL SENSOR ASSEMBLY)


    1. B0045RMC69
      *a

      Front view or wire harness connector

      (to Accelerator Pedal Sensor Assembly)

      Disconnect the accelerator pedal sensor assembly connector.

    2. Turn the engine switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A36-4 (VCPA) - A36-5 (EPA) Engine switch on (IG) 4.5 to 5.5 V
      A36-1 (VCP2) - A36-2 (EPA2) Engine switch on (IG) 4.5 to 5.5 V
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE ECM Click here

    OK

  4. REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY


    1. Replace the accelerator pedal sensor assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK WHETHER DTC OUTPUT RECURS (ACCELERATOR PEDAL SENSOR DTCS)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Clear the DTCs.

    5. Turn the engine switch off and wait for at least 30 seconds.

    6. Turn the engine switch on (IG).

    7. Turn the GTS on.

    8. Enter the following menus: Powertrain / Engine / Trouble Codes.

    9. Read the DTCs.

      Result
      Result Proceed to
      DTC P2138 are output A
      DTC is not output B

    A

    REPLACE ECM Click here

    B

    END