Code No. P0112: Intake Air Temperature Sensor Circuit Low Input










OPERATION




FUNCTION




TROUBLE JUDGMENT


Check Conditions
Judgment Criterion

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


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



  • Item 05: Intake air temperature sensor
OK: At ambient temperature (atmospheric temperature) or equivalent.

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: B-32 air flow sensor connector


Q. Is the check result normal?

Go to Step 3 .
Repair or replace the connector.

STEP 3. Check intake air temperature sensor itself.



  • Check intake air temperature sensor itself (Refer to ).

Q. Is the check result normal?

Go to Step 4 .
Replace the air flow sensor.

STEP 4. Perform voltage measurement at B-32 air flow sensor connector.



  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 1 and earth.
OK: 4.5 - 4.9 V

Q. Is the check result normal?

Go to Step 8 .
Go to Step 5 .

STEP 5. Connector check: D-217 engine-A/T-ECU connector


Q. Is the check result normal?

Go to Step 6 .
Repair or replace the connector.

STEP 6. Check harness between B-32 (terminal No. 1) air flow sensor connector and D-217 (terminal No. 99) engine-A/T-ECU connector.



  • Check output line for short circuit.

Q. Is the check result normal?

Go to Step 7 .
Repair the damaged harness wire.

STEP 7. M.U.T.-III data list



  • Item 05: Intake air temperature sensor
OK: At ambient temperature (atmospheric temperature) or equivalent.

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-A/T-ECU.

STEP 8. Perform resistance measurement at B-32 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 11 .
Go to Step 9 .

STEP 9. Connector check: D-217 engine-A/T-ECU connector


Q. Is the check result normal?


    Go to Step 10 .
Repair or replace the connector.

STEP 10. Check harness between B-32 (terminal No. 4) air flow sensor connector and D-217 (terminal No. 96) engine-A/T-ECU connector.



  • Check earthing line for damage.
note Before checking harness, check intermediate connector D-111, and repair if necessary.

Q. Is the check result normal?

Go to Step 7 .
Repair the damaged harness wire.

STEP 11. Connector check: D-217 engine-A/T-ECU connector


Q. Is the check result normal?

Go to Step 12 .
Repair or replace the connector.

STEP 12. Check harness between B-32 (terminal No. 1) air flow sensor connector and D-217 (terminal No. 99) engine-A/T-ECU connector.



  • Check output line for damage.

Q. Is the check result normal?

Go to Step 7 .
Repair the damaged harness wire.