Inspection Procedure 4: The Headlamp Automatic Levelling Warning is not Displayed.


caution Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.










OPERATION


When the height sensor or headlamp levelling unit is abnormal, the headlamp automatic levelling warning is displayed.

COMMENTS ON TROUBLE SYMPTOM


If the headlamp automatic levelling warning is not displayed, the combination meter, headlamp automatic levelling ECU, or the harness and connector(s) between the two may have a problem.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. Check of automatic levelling


Check that the automatic levelling operates normally.

Q. Is the check result normal?

Go to Step 2.

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

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


Perform the actuator test for the combination meter, and check that the headlamp automatic levelling warning is displayed (Refer to Combination Meter ).

Q. Is the check result normal?

Go to Step 3.

Replace the combination meter.

STEP 3. Connector check: C-03 combination meter connector, C-112 headlamp automatic levelling ECU connector


Q. Is the check result normal?

Go to Step 4.

Repair the defective connector.

STEP 4. Wiring harness check between the C-03 combination meter connector terminal No. 6 and the C-112 headlamp automatic levelling ECU connector terminal No. 8


note Prior to the wiring harness inspection, check intermediate connector C-38, and repair if necessary.

Q. Is the check result normal?

Go to Step 5.

Repair the wiring harness.

STEP 5. Voltage measurement at the C-03 combination meter connector


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage between the C-03 combination meter connector terminal No. 6 and the body earth.
OK: Battery voltage

Q. Is the check result normal?

Go to Step 6.

Troubleshoot the combination meter (Refer to Combination Meter ). On completion, go to Step 6.

STEP 6. Retest the system


Check that the headlamp automatic levelling warning display is illuminated under the illumination conditions.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Replace the headlamp automatic levelling ECU.