Inspection Procedure 10: One of the position lights, the license plate lights or the taillights does not illuminate: Diagnosis
Required Special Tools:
- MB992006: Extra fine probe
- MB991223: Harness set
- STEP 1. Bulb check
Check the bulb(s) of the light that does not illuminate.
Q: Is the check result normal?
- YES: Go to Step 2.
- NO: Replace the bulb(s) of the light that does not illuminate.
- STEP 2. Resistance measurement at the headlight assembly (position/side maker: LH) or (position/side maker: RH) connector, rear combination light (tail/side maker: LH) or (tail/side maker: RH) connector, license plate light (LH) or (RH) connector (ground terminal).
- Disconnect the connector, and measure at the wiring harness side.
- Measure the resistance between the connector terminal of light which does not illuminate and ground.
- Measure the resistance between the headlight assembly (position/side maker: LH) or (position/side maker: RH) connector (ground terminals) and ground.
- Measure the resistance between the rear combination light (tail/side maker: LH) or (tail/side maker: RH) connector (ground terminals) and ground.
- Measure the resistance between the license plate light (LH) or (RH) connector (ground terminals) and ground.
OK: The resistance should be 2 ohms or less
Q: Is the check result normal?
- YES: Go to Step 4.
- NO: Go to Step 3.
- STEP 3. Check of open circuit in ground lines between the headlight assembly (position/side maker: LH) or (position/side maker: RH) connector, rear combination light (tail/side maker: LH) or (tail/side maker: RH) connector, license plate light (LH) or (RH) connector and ground.
Q: Is the check result normal?
- YES: Go to Step 5.
- NO: Repair the connector(s) or wiring harness.
- STEP 4. Check of open circuit in (TAL1, TAR1, TAL2, TAR2) lines between the headlight assembly (position/side maker: LH) or (position/side maker: RH) connector, rear combination light (tail/side maker: LH) or (tail/side maker: RH) connector, license plate light (LH) or (RH) connector and ETACS-ECU connector.
Q: Is the check result normal?
- YES: Go to Step 5.
- NO: Repair the connector(s) or wiring harness.
- STEP 5. Retest the system
Check that the position light, taillight and license plate light illuminate normally.
Q: Is the check result normal?
The lights illuminate normally at both high and low beams.: The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
When the position lights do not illuminate: Replace the position light socket.
When the taillights do not illuminate: Replace the rear combination light socket.
When the license plate lights do not illuminate: Replace the license plate light socket.