LIGHTING SYSTEM PROBLEM SYMPTOMS TABLE

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

Headlight and Taillight
Symptom Suspected Area See page
One low beam headlight does not illuminate. H-LP LO (LH) fuse or H-LP LO (RH) fuse -
Discharge headlight bulb

Click here

Light control ECU

Click here

Headlight unit

Click here

Power distributor (Engine room junction block assembly)

Click here

Harness or connector -
Both left and right low beam headlights do not illuminate. Light control switch circuit

Click here

Headlight relay circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

One high beam headlight does not illuminate. H-LP HI (LH) fuse or H-LP HI (RH) fuse -
Bulb -
Power distributor (Engine room junction block assembly)

Click here

Harness or connector -
Both left and right high beam headlights do not illuminate. Light control switch circuit

Click here

Headlight solenoid circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

"High Flash" (passing function) headlight does not illuminate (high beam headlights are normal). Light control switch circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

Discharge headlight bulb flickers. Discharge headlight bulb

Click here

Harness or connector -
Light control ECU

Click here

Discharge headlight bulb is dark. Discharge headlight bulb

Click here

Harness or connector -
Light control ECU

Click here

Discharge headlight bulb does not come on at intervals. Discharge headlight bulb

Click here

Harness or connector -
Light control ECU

Click here

One front parking light does not illuminate. Bulb -
Harness or connector -
One rear taillight does not illuminate. Bulb -
Harness or connector -
One license plate light does not illuminate. Bulb -
Harness or connector -
All of the lights (rear taillights, parking lights and license plate lights) do not illuminate. TAIL fuse -
Light control switch circuit

Click here

Taillight relay circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

Stop Light
Symptom Suspected Area See page
One stop light does not illuminate. Rear combination light assembly

Click here

Harness or connector -
High mounted stop light does not illuminate. High mounted stop light assembly

Click here

Harness or connector -
All of lights do not illuminate. STOP fuse -
Stop light switch assembly

Click here

Harness or connector -
Front Fog Light
Symptom Suspected Area See page
One front fog light does not illuminate. Bulb -
Harness or connector -
Both left and right front fog lights do not illuminate (taillight is normal). FOG fuse -
Light control switch circuit

Click here

Front fog light circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

Rear Fog Light
Symptom Suspected Area See page
One rear fog light does not illuminate. Bulb -
Harness or connector -
Both left and right rear fog lights do not illuminate (taillight is normal). RR FOG fuse -
Light control switch circuit

Click here

Rear fog light circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

Back-up Light
Symptom Suspected Area See page
One back-up light does not illuminate. Bulb -
Harness or connector -
Both left and right back-up lights do not illuminate. GAUGE NO. 2 fuse -
Park/neutral position switch (for U760E)

Click here

Park/neutral position switch (for U760F)

Click here

Harness or connector -
Turn Signal Light
Symptom Suspected Area See page
One turn signal light does not operate. Bulb -
Harness or connector -
Side turn signal light does not operate. Side turn signal light assembly

Click here

Outer rear view mirror assembly

Click here

Harness or connector -
Outer mirror control ECU assembly

Click here

Turn signal lights do not operate in one direction. Headlight dimmer switch assembly (Turn signal light switch)

Click here

Turn signal flasher assembly

Click here

Harness or connector -
All turn signal lights do not operate. GAUGE NO. 1 fuse -
HAZ fuse -
Headlight dimmer switch assembly (Turn signal light switch)

Click here

Turn signal flasher assembly

Click here

Harness or connector -
All turn signal lights do not flash at the correct speed. Bulb -
Turn signal flasher assembly

Click here

Harness or connector -
Hazard Warning Light
Symptom Suspected Area See page
Hazard warning lights do not operate. HAZ fuse -
GAUGE NO. 1 fuse -
Hazard warning switch

Click here

Turn signal flasher assembly

Click here

Harness or connector -
Automatic Light Control System
Symptom Suspected Area See page
Automatic light control system does not operate. Check DTCs

Click here

Light control switch circuit

Click here

IG signal circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

Light Auto Turn-off System
Symptom Suspected Area See page
Light auto turn-off system does not operate. Light control switch circuit

Click here

Door courtesy switch circuit

Click here

IG signal circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

Daytime Running Light System
Symptom Suspected Area See page
Daytime running light system does not operate. Check CAN communication system -
Light control switch circuit

Click here

IG signal circuit

Click here

Parking brake switch circuit

Click here

Daytime running light relay circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here

Automatic High Beam System
Symptom Suspected Area See page
Inner rear view mirror assembly indicator light does not come on when the ignition switch is turned from off to ON. Inner rear view mirror power source circuit

Click here

Inner rear view mirror assembly

Click here

Inner rear view mirror assembly indicator light remains on when the inner rear view mirror assembly AUTO switch is pressed. Inner rear view mirror assembly

Click here

Inner rear view mirror assembly indicator light flashes. Perform operation check

Click here

Inner rear view mirror assembly

Click here

Automatic high beam indicator light does not come on when the automatic high beam system is in standby mode (automatic light control system operates normally). Perform operation check

Click here

Light control switch circuit

Click here

Combination meter assembly

Click here

Automatic high beam system does not operate (automatic high beam indicator light flashes). Check DTCs

Click here

Combination meter assembly

Click here

Automatic high beam system does not operate (automatic high beam indicator light is on or off). Inner rear view mirror assembly (Camera detection malfunction*1)

Click here

Inner rear view mirror assembly (Aiming misalignment*2)

Click here

Note

*1: Camera detection malfunctions can be detected using the GTS. Under the following conditions, if the camera built into the inner rear view mirror assembly cannot detect other vehicles or lights correctly, it will stop automatic high beam control and turn off the automatic high beam indicator light:


  • When the front windshield is not clear (ice, snow or frost on the glass).


  • When the front windshield is dirty (sand, mud, water stains or bugs are on the glass).

*2: Aiming misalignment of the camera can be detected using the GTS. Under the following conditions, the camera built in to the rear view mirror assembly cannot adjust its center point:


  • When the inner rear view mirror assembly is on an angle due to mis-installation or damage to the camera.


  • When the automatic aiming adjusting function of the mirror does not work correctly.

If the camera aiming is misaligned, check the following conditions:


  • Check if the vehicle is inclined.


  • Check if the windshield glass is installed correctly.


  • Check if the inner rear view mirror assembly is installed correctly.


  • Check if there is deformation of the camera or stay of the inner rear view mirror assembly.

Automatic Headlight Beam Level Control
Symptom Suspected Area See page
Headlight beam level control indicator light flashes. Check DTCs

Click here

Indicator circuit

Click here

Headlight leveling ECU assembly

Click here

Headlight beam level control does not operate (indicator light is off). Check the FAIL-SAFE function

Click here

Check DTCs

Click here

Headlight leveling ECU power source circuit

Click here

Headlight signal circuit

Click here

Headlight beam level control actuator circuit

Click here

Speed signal circuit

Click here

Headlight leveling ECU assembly

Click here

Headlight beam level control system indicator light does not come on when turning the ignition switch to ON. Indicator circuit

Click here

Headlight leveling ECU assembly

Click here

Combination meter assembly

Click here

DTC information cannot be detected. Diagnosis circuit

Click here

Headlight leveling ECU assembly

Click here

Initialization cannot be performed. Check DTCs

Click here

LVL terminal circuit

Click here

Headlight leveling ECU assembly

Click here

Note


  • Initialize the headlight leveling ECU assembly after the vehicle height changes due to replacement of the suspension or after performing such operations as removal and reinstallation or replacement of the rear height control sensor sub-assembly RH.


  • When the headlight leveling ECU assembly is replaced, the initialization is also necessary.

Door Mirror Foot Light
Symptom Suspected Area See page
One door mirror foot light does not illuminate. Outer mirror light assembly

Click here

Door mirror foot light circuit

Click here

Outer mirror control ECU assembly

Click here

Both left and right door mirror foot lights do not illuminate. CAN communication system

Click here

Power door lock control system

Click here

Wireless door lock control system (w/ Smart Entry and Start System)

Click here

Wireless door lock control system (w/o Smart Entry and Start System)

Click here

Smart entry and start system (for Entry Function)

Click here

Door mirror foot light circuit

Click here

Door unlock detection switch circuit

Click here

Main body ECU (Driver side junction block assembly)

Click here