Inspection Procedure 4: The Headlamp Automatic Levelling Warning Lamp does not Illuminate.


caution Whenever the ECU is replaced, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.














OPERATION


If the height sensor or the headlamp levelling unit is defective, the headlamp automatic levelling warning lamp illuminates.

COMMENTS ON TROUBLE SYMPTOM


If the headlamp automatic levelling warning lamp does not illuminate under the illumination conditions, the warning lamp power supply system may be defective, or the combination meter, the headlamp automatic levelling-ECU, or wiring harness and connectors between the two may be defective.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. Check the automatic levelling


Check that the automatic levelling operates normally.

Q. Is the check result normal?

Go to Step 2.

Inspection Procedure 2 "Neither right nor left automatic levelling operates." Refer to .

STEP 2. M.U.T.-III actuator test


Perform the actuator test for the combination meter, and check that the headlamp automatic levelling warning lamp illuminates (Refer to Combination Meter - Troubleshooting ).

Q. Is the check result normal?

Go to Step 3.

Replace the combination meter.

STEP 3. Connector check: D-04 Combination meter connector and D-125 headlamp automatic levelling-ECU connector


Q. Is the check result normal?

Go to Step 4.

Repair the defective connector.

STEP 4. Check the wiring harness between D-04 combination meter connector (terminal No. 12) and D-125 headlamp automatic levelling-ECU connector (terminal No. 8).


Q. Is the check result normal?

Go to Step 5.

Repair the wiring harness.

STEP 5. Voltage measurement at D-02 combination meter connector.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch to the "ON" position.
(3)Voltage between D-02 combination meter connector (terminal No.42) and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 7.

Go to Step 6.

STEP 6. Check the harness wire between ignition switch (IG1) and D-02 combination meter connector (terminal No.42).


note Prior to the wiring harness inspection, check junction block connectors D-403 and D-405, and repair if necessary.

Q. Is the check result normal?

Go to Step 7.

Repair the wiring harness.

STEP 7. Retest the system.


Check that the headlamp automatic levelling warning lamp illuminates under the illumination conditions.

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 headlamp automatic levelling-ECU.