Code No. P2127: Accelerator Pedal Position Sensor (sub) Circuit Low Input










OPERATION




FUNCTION




TROUBLE JUDGMENT


Check Conditions
Judgment Criterion

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III data list



  • Refer to Data List Reference Table .

    1. Item 10: Accelerator pedal position sensor (sub)

Q. Is the check result normal?

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Go to Step 2.

STEP 2. Connector check: D-202 accelerator pedal position sensor connector


Q. Is the check result normal?

Go to Step 3.
Repair or replace the connector.

STEP 3. Perform voltage measurement at D-202 accelerator pedal position sensor connector.



  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 4 and earth.
OK: 4.9 - 5.1 V

Q. Is the check result normal?

Go to Step 7.
Go to Step 4.

STEP 4. Connector check: D-215 engine-ECU connector


Q. Is the check result normal?

Go to Step 5.
Repair or replace the connector.

STEP 5. Check harness between D-202 (terminal No. 4) accelerator pedal position sensor connector and D-215 (terminal No. 112) engine-ECU connector.



  • Check power supply line for open/short circuit.

Q. Is the check result normal?

Go to Step 6.
Repair the damaged harness wire.

STEP 6. M.U.T.-III data list



  • Refer to Data List Reference Table .

    1. Item 10: Accelerator pedal position sensor (sub)

Q. Is the check result normal?

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Replace the engine-ECU. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - Precautions Before Service - How to Perform Chassis Number Writing ). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ).

STEP 7. Perform resistance measurement at D-202 accelerator pedal position sensor connector.



  • Disconnect connector, and measure at harness side.
  • Resistance between terminal No. 5 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?

Go to Step 10.
Go to Step 8.

STEP 8. Connector check: D-215 engine-ECU connector


Q. Is the check result normal?


    Go to Step 9.
Repair or replace the connector.

STEP 9. Check harness between D-202 (terminal No. 5) accelerator pedal position sensor connector and D-215 (terminal No. 114) engine-ECU connector.



  • Check earthing line for damage.

Q. Is the check result normal?

Go to Step 6.
Repair the damaged harness wire.

STEP 10. Connector check: D-215 engine-ECU connector


Q. Is the check result normal?

Go to Step 11.
Repair or replace the connector.

STEP 11. Perform voltage measurement at D-202 accelerator pedal position sensor connector.



  • Use special tool test harness (MB991658) to connect connector, and measure at pick-up harness.
  • Ignition switch: ON
  • Voltage between terminal No. 6 and earth.
OK: 0.2 - 0.8 V

Q. Is the check result normal?

Go to Step 15.
Go to Step 12.

STEP 12. Connector check: D-215 engine-ECU connector


Q. Is the check result normal?

Go to Step 13.
Repair or replace the connector.

STEP 13. Check harness between D-202 (terminal No. 6) accelerator pedal position sensor connector and D-215 (terminal No. 113) engine-ECU connector.



  • Check output line for short circuit.

Q. Is the check result normal?

Go to Step 14.
Repair the damaged harness wire.

STEP 14. Check harness between D-202 (terminal No. 4) accelerator pedal position sensor connector and D-215 (terminal No. 112) engine-ECU connector.



  • Check power supply line for damage.

Q. Is the check result normal?

Replace the accelerator pedal assembly.
Repair the damaged harness wire.

STEP 15. Check harness between D-202 (terminal No. 6) accelerator pedal position sensor connector and D-215 (terminal No. 113) engine-ECU connector.



  • Check output line for open circuit and damage.

Q. Is the check result normal?

Go to Step 6.
Repair the damaged harness wire.