Description

Headlight (LH) circuit malfunction

Detection condition

• The auto leveling control module detected an open circuit in the headlight (LH) circuit during the headlight LO on control with the ignition switched ON (engine off or on).

Fail-safe

• Control of the headlight auto leveling system is continued.

Possible cause

• DTCs are stored in the electrical supply unit (ESU).

• Headlight LO (LH) circuit malfunction

• Front combination light (LH) connector or terminal malfunction

• Auto leveling control module connector or terminal malfunction

• Short to ground in wiring harness between auto leveling control module terminal J and front combination light (LH) terminal N

• Open circuit in wiring harness between auto leveling control module terminal J and front combination light (LH) terminal N

• Front combination light (LH) malfunction

• Auto leveling control module malfunction

Step

Inspection

Action

1

• Retrieve the electrical supply unit (ESU) DTCs using the M-MDS.

  (See DTC INSPECTION [ELECTRICAL SUPPLY UNIT (ESU)].)

• Are any other DTCs displayed?

Yes

Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.

(See DTC TABLE [ELECTRICAL SUPPLY UNIT (ESU)].)

No

Go to the next step.

2

• Switch the ignition off.

• Disconnect the negative battery cable.

  (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.)

• Disconnect the front combination light (LH) connector.

• Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.

• Is the connector normal?

Yes

Go to the next step.

No

Repair or replace the connector, then go to Step 7.

3

• Disconnect the auto leveling control module connector.

• Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.

• Is the connector normal?

Yes

Go to the next step.

No

Repair or replace the connector, then go to Step 7.

4

• Verify that the front combination light (LH) and auto leveling control module connectors are disconnected.

• Inspect for continuity between front combination light (LH) terminal N (wiring harness-side) and body ground.

• Is there continuity?

Yes

Refer to the wiring diagram and verify whether or not there is a common connector between auto leveling control module terminal J and front combination light (LH) terminal N.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has a short to ground.

Go to Step 7.

No

Go to the next step.

5

• Verify that the front combination light (LH) and auto leveling control module connectors are disconnected.

• Inspect the wiring harness for continuity between auto leveling control module terminal J (wiring harness-side) and front combination light (LH) terminal N (wiring harness-side).

• Is there continuity?

Yes

Go to the next step.

No

Refer to the wiring diagram and verify whether or not there is a common connector between auto leveling control module terminal J and front combination light (LH) terminal N.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has an open circuit.

Go to Step 7.

6

• Always reconnect all disconnected connectors.

• Connect the negative battery cable.

  (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.)

• Clear the DTC for the auto leveling control module using the M-MDS.

  (See CLEARING DTC [AUTO LEVELING CONTROL MODULE].)

• Operate the light switch to the HEAD position and the dimmer switch to the LO position.

• Retrieve the auto leveling control module DTCs using the M-MDS.

  (See DTC INSPECTION [AUTO LEVELING CONTROL MODULE].)

• Is the same DTC displayed?

Yes

Replace the front combination light (LH), then go to the next step.

(See FRONT COMBINATION LIGHT REMOVAL/INSTALLATION.)

No

Go to Step 8.

7

• Always reconnect all disconnected connectors.

• Connect the negative battery cable.

  (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.)

• Clear the DTC for the auto leveling control module using the M-MDS.

  (See CLEARING DTC [AUTO LEVELING CONTROL MODULE].)

• Operate the light switch to the HEAD position and the dimmer switch to the LO position.

• Retrieve the auto leveling control module DTCs using the M-MDS.

  (See DTC INSPECTION [AUTO LEVELING CONTROL MODULE].)

• Is the same DTC displayed?

Yes

Repeat the inspection from Step 1.

• If the malfunction recurs, replace the auto leveling control module.

  (See AUTO LEVELING CONTROL MODULE REMOVAL/INSTALLATION.)

Go to the next step.

No

Go to the next step.

8

• Are any other DTCs displayed?

Yes

Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.

(See DTC TABLE [AUTO LEVELING CONTROL MODULE].)

No

DTC troubleshooting completed.