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DTC P2123-00: Throttle/Pedal Position Sensor/Switch "D" Circuit High [07/2015 - 08/2018]: Procedure

  1. DETERMINE IF APP SENSOR NO. 1 OR WIRING HARNESS MALFUNCTION 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Accelerator pedal position sensor 1.

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Accelerator pedal position sensor 1
    5. Verify the Accelerator pedal position sensor 1 PID value.
    6. Is the Accelerator pedal position sensor 1 PID value 5 V or B+?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  5

    Result: 

    No 

    See step  2

  2. INSPECT APP SENSOR CONNECTOR CONDITION 
    1. Switch the ignition off.
    2. Disconnect the APP sensor connector.
    3. Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
    4. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  15

    Result: 

    No 

    See step  3

  3. INSPECT ECM CONNECTOR CONDITION 
    1. Disconnect the ECM connector.
    2. Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
    3. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  14

    Result: 

    No 

    See step  4

  4. INSPECT APP SENSOR NO. 1 
    1. Reconnect all disconnected connectors.
    2. Inspect the APP sensor No. 1.

      Refer to INSPECTION [07/2015 - ]

    3. Is there any malfunction?

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  7

    Result: 

    Yes 

    See step  13

  5. INSPECT APP SENSOR NO. 1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
    1. Switch the ignition off.
    2. Disconnect the APP sensor connector.
    3. Connect the Techstream to the DLC3.
    4. Turn the ignition switch to ON.
    5. Turn the Techstream on.
    6. Enter the following menus: Powertrain / Engine / Data List / Accelerator pedal position sensor 1.

      Refer to ON-BOARD DIAGNOSTIC TEST [07/2015 - ]

      Powertrain > Engine > Data List 

      Tester Display
      Accelerator pedal position sensor 1
    7. Verify the Accelerator pedal position sensor 1 PID value.
    8. Is the Accelerator pedal position sensor 1 PID value 5 V or B+?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  12

    Result: 

    No 

    See step  6

  6. INSPECT APP SENSOR NO. 1 GROUND CIRCUIT FOR OPEN CIRCUIT 
    1. Verify that the APP sensor connector is disconnected.
    2. Switch the ignition off.
    3. Disconnect the ECM connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E7-3 - A42-57 Always Below 1 Ω

      Result

      Result
      Yes
      No

    Result: 

    No 

    See step  10

    Result: 

    Yes 

    See step  11

  7. VERIFY DTC TROUBLESHOOTING COMPLETED 
    1. Always reconnect all disconnected connectors.
    2. Clear the DTC from the ECM memory using the Techstream.

      Refer to AFTER REPAIR PROCEDURE [07/2015 - ]

      Powertrain > Engine > Clear DTCs 

    3. Perform the KOEO or KOER self test.

      Refer to ON-DEMAND SELF-TEST/KEY-ON ENGINE RUNNING SELF-TEST [07/2015 - ]

      Powertrain > Engine > Utility 

      Tester Display
      Key-On Engine Running Self-Test

      Powertrain > Engine > Utility 

      Tester Display
      On-Demand Self-Test
    4. Is the same DTC present?

      Result

      Result
      Yes
      No

    Result: 

    Yes 

    See step  9

    Result: 

    No 

    See step  8

  8. VERIFY AFTER REPAIR PROCEDURE 
    1. Perform the "AFTER REPAIR PROCEDURE".

      Refer to AFTER REPAIR PROCEDURE [07/2015 - ]

    2. Are any DTCs present?

      Result

      Result
      Yes
      No

    Result: 

    No 

    DTC TROUBLESHOOTING COMPLETED. 

    Result: 

    Yes 

    GO TO THE APPLICABLE DTC INSPECTION. 

    1. Refer to DIAGNOSTIC TROUBLE CODE CHART [07/2015 - 08/2018]
  9. REPEAT THE INSPECTION FROM STEP 1. 
    1. If the malfunction recurs, replace the ECM.

      Refer to REMOVAL [07/2015 - ]

    2. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  8

  10. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN APP SENSOR TERMINAL E7-3 AND ECM TERMINAL A42-57. 

    If there is a common connector: 

    • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
    • Repair or replace the malfunctioning part.

    If there is no common connector: 

    • Repair or replace the wiring harness which has an open circuit.
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

  11. REPLACE THE ACCELERATOR PEDAL. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

  12. REFER TO THE WIRING DIAGRAM AND VERIFY WHETHER OR NOT THERE IS A COMMON CONNECTOR BETWEEN APP SENSOR TERMINAL E7-2 AND ECM TERMINAL A42-42. 

    If there is a common connector: 

    • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
    • Repair or replace the malfunctioning part.

    If there is no common connector: 

    • Repair or replace the wiring harness which has a short to power supply.
    1. Go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

  13. REPLACE THE ACCELERATOR PEDAL. 
    1. Refer to REMOVAL [07/2015 - ]
    2. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

  14. REPAIR OR REPLACE THE CONNECTOR AND/OR TERMINALS. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

  15. REPAIR OR REPLACE THE CONNECTOR AND/OR TERMINALS. 
    1. Then go to the next step.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

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