Code No. P0100: Air Flow Sensor System




OPERATION



FUNCTION



TROUBLE JUDGMENT


Check Condition
Judgment Criterion
or

PROBABLE CAUSE



DIAGNOSIS PROCEDURE

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

  • Refer to Data List Reference Table .

    1. Item No. 80: Air flow sensor

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: A-136 air flow sensor connector



Q. Is the check result normal?

Go to Step 3 .

Repair.

STEP 3. Perform voltage measurement at A-136 air flow sensor connector.


  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 2 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 5 .

Go to Step 4 .

STEP 4. Connector check: B-206 engine control relay connector


Q. Is the check result normal?


    Check intermediate connector B-212, and repair if necessary. If intermediate connector is normal, check and repair harness between A-136 (terminal No. 2) air flow sensor connector and B-206 (terminal No. 4) engine control relay connector.

    • Check power supply line for open/short circuit.

Repair.

STEP 5. Perform resistance measurement at A-136 air flow sensor connector.


  • Disconnect connector, and measure at harness side.
  • Resistance between terminal No. 4 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?

Go to Step 9 .

Go to Step 6 .

STEP 6. Connector check: A-35 engine-ECU connector

Q. Is the check result normal?

Go to Step 7 .

Repair.

STEP 7. Check harness between A-136 (terminal No. 4) air flow sensor connector and A-35 (terminal No. 102) engine-ECU connector.



  • Check earthing line for open circuit.

Q. Is the check result normal?

Go to Step 8 .

Repair.

STEP 8. M.U.T.-III data list

  • Refer to Data List Reference Table .

    1. Item No. 80: Air flow sensor

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 engine-ECU then perform the variant coding (Refer to GROUP 00 - Precautions Before Service -How to Perform Variant Coding ).

STEP 9. Connector check: A-35 engine-ECU connector.

Q. Is the check result normal?

Go to Step 10 .

Repair.

STEP 10. Check harness between A-136 (terminal No. 3) air flow sensor connector and A-35 (terminal No. 126) engine-ECU connector.



  • Check output line for open/short circuit and damage.

Q. Is the check result normal?

Go to Step 11 .

Repair.

STEP 11. Connector check: B-206 engine control relay connector

Q. Is the check result normal?

Go to Step 12 .

Repair.

STEP 12. Check harness between A-136 (terminal No. 2) air flow sensor connector and B-206 (terminal No. 4) engine control relay connector.


note Before checking harness, check intermediate connector B-212, and repair if necessary.

  • Check power supply line for damage.

Q. Is the check result normal?

Go to Step 13 .

Repair.

STEP 13. M.U.T.-III data list

  • Refer to Data List Reference Table .

    1. Item No. 80: Air flow sensor

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 14 .

STEP 14. Replace air flow sensor.

  • After replacing the air flow sensor, re-check the trouble symptoms.

Q. Is the check result normal?
Replace the engine-ECU then perform the variant coding (Refer to GROUP 00 - Precautions Before Service - How to Perform Variant Coding ).
Check end.