No.1 AUTO LEVELING WARNING LIGHT ILLUMINATES WHEN THE IGNITION SWITCH TURNED TO ON POSITION

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1
Auto leveling warning light illuminates when the ignition switch turned to ON position
POSSIBLE CAUSE
•  Headlight auto leveling function related electrical part malfunction
―  Auto leveling sensor related part malfunction
•  Auto leveling control unit power supply voltage excessive low
•  Auto leveling sensor signal voltage excessive high or low
•  Front auto leveling sensor malfunction
•  Rear auto leveling sensor malfunction
―  Malfunction in headlight leveling actuator (left or right) integrated in front combination light.
•  Malfunction in wiring harness between auto leveling control unit and headlight leveling actuator.
•  Headlight leveling actuator (left or right) malfunction.
―  Auto leveling control unit malfunction
―  Auto leveling control unit power supply voltage is excessive high
―  Vehicle speed signal malfunction.
•  DSC HU/CM malfunction
•  Open circuit between DSC HU/CM terminal AA and auto leveling control unit terminal W
•  Auto leveling warning light control circuit malfunction
―  Instrument cluster malfunction
―  Short to ground between instrument cluster terminal 2J and auto leveling control unit terminal U

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY THAT THE FRONT AND REAR AUTO LEVELING SENSOR INSTALLATION
•  Verify that the front and rear auto leveling sensor installation.
•  Is there any bend, damage or dislocated link at the bracket?
Yes
Repair or replace malfunctioning part.
No
Go to the next step.
2
INSPECT AUTO LEVELING CONTROL UNIT POWER SUPPLY VOLTAGE
•  Turn the ignition switch to ON position.
•  Measure the voltage between auto leveling control unit terminals A and ground.
•  Is the voltage B+?
Yes
Go to the next step.
No
Repair or replace for open circuit between the auto leveling control unit terminal A and the ignition switch.
3
INSPECT AUTO LEVELING CONTROL UNIT GROUND CIRCUIT FOR OPEN
•  Turn the ignition switch to OFF.
•  Disconnect the auto leveling control unit connector.
•  Verify that continuity between auto leveling control unit terminal X and ground.
•  Is there continuity?
Yes
Connect the auto leveling control unit connector, then go to Step 5.
No
Go to the next step.
4
INSPECT GROUND POINT
•  Verify that the ground point for auto leveling control unit.
•  Is there loose or poor connection at ground point?
Yes
Retighten the ground point.
No
Repair or replace for open circuit between auto leveling control unit terminal X and ground.
5
INSPECT IF MALFUNCTION IS IN FRONT AUTO LEVELING SENSOR OR ELSEWHERE
•  Turn the ignition switch to ON position.
•  Turn the headlight to ON.
•  Measure voltage between auto leveling control unit terminal K and ground.
•  Is the voltage 0.25—4.75 V?
Yes
Go to the next step.
No
Go to Step 9.
6
INSPECT IF MALFUNCTION IS IN REAR AUTO LEVELING SENSOR OR ELSEWHERE
•  Turn the ignition switch to ON position.
•  Turn the headlight to ON.
•  Measure voltage between auto leveling control unit terminal I and ground.
•  Is the voltage 0.25—4.75 V?
Yes
Go to Step 11.
No
Go to the next step.
7
INSPECT REAR AUTO LEVELING SENSOR SIGNAL CIRCUIT
•  Inspect the wiring harness between auto leveling control unit terminal I and rear auto leveling sensor terminal B.
•  Is there open or short circuit detected?
Yes
Repair or replace for open or short circuit.
No
Go to the next step.
8
INSPECT REAR AUTO LEVELING SENSOR
•  Inspect the rear auto leveling sensor.
•  Is the rear auto leveling sensor normal?
Yes
Repair or replace for open circuit at following.
•  Between auto leveling control unit terminal C and rear auto leveling sensor terminal A
•  Between auto leveling control unit terminal P and rear auto leveling sensor terminal C
No
Replace the rear auto leveling sensor.
(See REAR AUTO LEVELING SENSOR REMOVAL/INSTALLATION.)
9
INSPECT IF MALFUNCTION IS IN REAR AUTO LEVELING SENSOR POWER OR GROUND CIRCUIT OR ELSEWHERE
•  Turn the ignition switch to ON position.
•  Turn the headlight to ON.
•  Measure voltage between auto leveling control unit terminal I and ground.
•  Is the voltage 0.25—4.75 V?
Yes
Go to the next step.
No
Repair or replace for open circuit at following.
•  Between auto leveling control unit terminal C and front auto leveling sensor terminal A
•  Between auto leveling control unit terminal C and rear auto leveling sensor terminal A
•  Between auto leveling control unit terminal P and front auto leveling sensor terminal C
•  Between auto leveling control unit terminal P and rear auto leveling sensor terminal C
10
INSPECT FRONT AUTO LEVELING SENSOR SIGNAL CIRCUIT
•  Inspect the wiring harness between auto leveling control unit terminal K and front auto leveling sensor terminal B.
•  Is there open or short circuit detected?
Yes
Repair or replace for open or short circuit.
No
Inspect the front auto leveling sensor.
(See FRONT AUTO LEVELING SENSOR INSPECTION.)
If not normal, replace the front auto leveling sensor.
(See FRONT AUTO LEVELING SENSOR REMOVAL/INSTALLATION.)
11
INSPECT IF MALFUNCTION IS IN AUTO LEVELING WARNING LIGHT CONTROL CIRCUIT OR ELSEWHERE
•  Turn the ignition switch to OFF.
•  Disconnect the auto leveling control unit and instrument cluster connectors.
•  Verify continuity between auto leveling control unit terminal U and ground.
•  Is there continuity?
Yes
Repair or replace for short to ground.
No
Go to the next step.
12
INSPECT IF THE MALFUNCTION IS IN INSTRUMENT CLUSTER
•  Turn the ignition switch to OFF.
•  Connect the instrument cluster connector (with auto leveling control unit connector disconnected).
•  Short to ground at auto leveling control unit terminal U using the jumper wire.
•  Turn the ignition switch to ON position.
•  Does the auto leveling warning light illuminate?
Yes
Go to the next step.
No
Replace the instrument cluster.
(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
13
INSPECT WIRING HARNESS BETWEEN AUTO LEVELING CONTROL UNIT AND HEADLIGHT LEVELING ACTUATOR
Verify if there is an open or short circuit in the following wiring harnesses and connectors.
Right side
•  Auto leveling control unit terminal B and headlight leveling actuator (right) terminal F
•  Auto leveling control unit terminal T and headlight leveling actuator (right) terminal H
•  Auto leveling control unit terminal E and headlight leveling actuator (right) terminal G
Left side
•  Auto leveling control unit terminal B and headlight leveling actuator (left) terminal F
•  Auto leveling control unit terminal T and headlight leveling actuator (left) terminal H
•  Auto leveling control unit terminal G and headlight leveling actuator (left) terminal G
Is there any open or short circuit in the wiring harness?
Yes
Repair the open or short circuit or replace the wiring harness.
No
Go to the next step.
14
DETERMINE IF MALFUNCTION CAUSE IS HEADLIGHT LEVELING ACTUATOR
•  Prepare and install a front combination light (left or right) which has a headlight leveling actuator that operates normally.
•  After installing the left or right front combination light, does the auto leveling warning light turn off?
Yes
Replace the front combination light on the side which the auto leveling warning light turned off.
No
Go to the next step.
15
VERIFY THE WIRING HARNESS FOR CONTINUITY BETWEEN THE DSC HU/CM AND THE AUTO LEVELING CONTROL UNIT.
•  Verify that continuity between DSC HU/CM terminal AA and auto leveling control unit terminal W.
•  Is there continuity?
Yes
Auto leveling control unit replacement.
(See AUTO LEVELING CONTROL UNIT REMOVAL/INSTALLATION.)
No
Repair or replace the wiring harness.