Inspection Procedure 4
Inspection Procedure 4: The Headlight Automatic Leveling Warning Is Not Displayed.CAUTION: Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
Headlight Automatic Leveling Warning Display Circuit (Part 1):
Headlight Automatic Leveling Warning Display Circuit (Part 2):
OPERATION
When the height sensor or headlight leveling unit is abnormal, the headlight automatic leveling warning is displayed.
COMMENTS ON TROUBLE SYMPTOM
If the headlight automatic leveling warning is not displayed, the combination meter, headlight automatic leveling-ECU, or the harness and connector(s) between the two may have a problem.
TECHNICAL DESCRIPTION (COMMENT)
- Malfunction of the headlight automatic leveling-ECU
- Malfunction of combination meter
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Check of automatic leveling.
Check that the automatic leveling operates normally.
Q: Is the check result normal?
YES : Go to Step 2.
NO : Refer to Inspection Procedure 2 "Neither right nor left automatic leveling operates." Inspection Procedure 2
STEP 2. Using scan tool MB991958, check other system actuator test.
Perform the actuator test for the combination meter, and check that the headlight automatic leveling warning is displayed .
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958. Refer to "How to connect scan tool (M.U.T.-III)." Scan Tool Connecting
2. Connect scan tool MB991958 to the data link connector.
3. Turn the ignition switch to the "ON" position.
4. Set scan tool MB991958 to the actuator test mode.
- " Item 8: Indicator2
5 Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result normal?
YES : Go to Step 3.
NO : Replace the combination meter.
STEP 3. Check combination meter connector C-03, headlight automatic leveling-ECU connector C-110 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is combination meter connector C-03, headlight automatic leveling-ECU connector C-110 in good condition?
YES : Go to Step 4.
NO : Repair the damaged parts.
STEP 4. Check wiring harness between combination meter connector C-03 (terminal No. 6/20) and the headlight automatic leveling-ECU connector C-110 (terminal No. 8/9).
NOTE: Prior to the wiring harness inspection, check intermediate connector C-34, and repair if necessary.
Q: Are the wiring harness between combination meter connector C-03 (terminal No. 6/20) and the headlight automatic leveling-ECU connector C-110 (terminal No. 8/9) in good condition?
YES : Go to Step 5.
NO : Repair the wiring harness.
STEP 5. Retest the system
Check that the headlight automatic leveling warning display is illuminated under the illumination conditions.
Q: Is the check result normal?
YES : The trouble can be an intermittent malfunction (Refer to general (body and chassis) - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction).
NO : Replace the headlight automatic leveling-ECU.