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 (for Halogen Headlight)
Symptom	Suspected Area	See page
One low beam headlight does not illuminate.	Bulb	-
	No. 1 integration relay	Click here
	Harness or connector	-
Both left and right low beam headlights do not illuminate.	Headlight dimmer switch circuit	Click here
	Low beam headlight circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
One high beam headlight does not illuminate.	H-LP LH HI fuse or H-LP RH HI fuse	-
	Bulb	-
	No. 1 integration relay	Click here
	Harness or connector	-
Both left and right high beam headlights do not illuminate.	H-LP HI MAIN FUSE	-
	Headlight dimmer switch circuit	Click here
	High beam headlight circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
"High Flash" (passing function) headlight does not illuminate (high beam headlights are normal).	Headlight dimmer switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
One front parking light does not illuminate.	Bulb	-
One front parking light does not illuminate.	Harness or connector	-
One rear taillight does not illuminate.	Rear combination light assembly	Click here
One rear taillight does not illuminate.	Harness or connector	-
One license plate light does not illuminate.	Bulb	-
One license plate light does not illuminate.	Harness or connector	-
All of the lights (rear taillights, parking lights, and license plate lights) do not illuminate.	TAIL fuse	-
	Headlight dimmer switch circuit	Click here
	Taillight relay circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Headlight and Taillight (for LED Headlight)
Symptom	Suspected Area	See page
One low beam headlight does not illuminate.	Check DTCs	-
	Light control ECU	Click here
	No. 1 integration relay	Click here
	Headlight unit	Click here
	Harness or connector	-
Both left and right low beam headlights do not illuminate.	Check DTCs	Click here
	Headlight dimmer switch circuit	Click here
	Low beam headlight circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
"High Flash" (passing function) headlight does not illuminate (high beam headlights are normal).	Headlight dimmer switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
One front parking light does not illuminate.	Bulb	-
One front parking light does not illuminate.	Harness or connector	-
One rear taillight does not illuminate.	Rear combination light assembly	Click here
One rear taillight does not illuminate.	Harness or connector	-
One license plate light does not illuminate.	Bulb	-
One license plate light does not illuminate.	Harness or connector	-
All of the lights (rear taillights, parking lights and license plate lights) do not illuminate.	TAIL fuse	-
	Headlight dimmer switch circuit	Click here
	Taillight relay circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
LED headlight warning light does not illuminate (LED headlights are normal).	Harness or connector	-
	Light control ECU	Click here
	Headlight unit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
	Meter circuit plate	Click here

Stop Light
Symptom	Suspected Area	See page
One side stop light does not illuminate.	Rear combination light assembly	Click here
One side stop light does not illuminate.	Harness or connector	-
High mounted stop light does not illuminate.	Center stop light assembly	Click here
	Center stop light wire harness	Click here
	Harness or connector	-
All of the stop lights do not illuminate.	STOP fuse	-
	Stop light switch assembly	Click here
	Stop light control relay	Click here
	Harness or connector	-
Stop lights remain on.	Electronically controlled brake system	Click here
	Stop light switch assembly	Click here
	Stop light control ECU assembly	Click here
	Harness or connector	-
	Skid control ECU (for LHD)	Click here
	Skid control ECU (for RHD)	Click here

Front Fog Light (w/ Front Fog Light)
Symptom	Suspected Area	See page
One front fog light does not illuminate.	Bulb	-
One front fog light does not illuminate.	Harness or connector	-
Both left and right front fog lights do not illuminate (taillights are normal).	FR FOG fuse	-
	Headlight dimmer switch circuit	Click here
	Front fog light circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Rear Fog Light
Symptom	Suspected Area	See page
Rear fog light does not illuminate.	Bulb	-
	RR FOG fuse	-
	Headlight dimmer switch circuit	Click here
	Rear fog light circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Back-up Light
Symptom	Suspected Area	See page
One back-up light does not illuminate.	Bulb	-
One back-up light does not illuminate.	Harness or connector	-
Both left and right back-up lights do not illuminate.	Back-up light circuit	Click here
	Harness or connector	-
	Power management control ECU	Click here

Turn Signal Light
Symptom	Suspected Area	See page
One turn signal light does not operate (except side turn signal lights).	Bulb	-
	Harness or connector	-
Turn signal lights do not operate in one direction.	Headlight dimmer switch assembly (Turn signal light switch)	Click here
	Meter circuit plate	Click here
	Harness or connector	-
All turn signal lights do not operate.	ECU-IG NO. 2 fuse	-
	HAZ fuse	-
	Headlight dimmer switch assembly (Turn signal light switch)	Click here
	Meter circuit plate	Click here
	Harness or connector	-
All turn signal lights do not flash at the correct speed.	Bulb	-
	Meter circuit plate	Click here
	Harness or connector	-

Hazard Warning Light
Symptom	Suspected Area	See page
Hazard warning lights do not operate.	Hazard warning switch circuit	Click here
Hazard warning lights do not operate.	Meter circuit plate	Click here
Hazard warning lights operate when the hazard warning switch is not turned on.	Electronically controlled brake system	Click here
	Hazard warning switch	Click here
	Meter circuit plate	Click here
	Harness or connector	-
	Skid control ECU (for LHD)	Click here
	Skid control ECU (for RHD)	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Automatic Light Control System
Symptom	Suspected Area	See page
Automatic light control system does not operate.	Check DTCs	Click here
	Headlight dimmer switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Light Auto Turn-off System (for European Models)
Symptom	Suspected Area	See page
Light auto turn-off system does not operate. (Light control switch is in TAIL or HEAD position)	Headlight dimmer switch circuit	Click here
	IG signal circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
Light auto turn-off system does not operate. (Light control switch is in AUTO position)	Headlight dimmer switch circuit	Click here
	IG signal circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Light Auto Turn-off System (except European Models)
Symptom	Suspected Area	See page
Light auto turn-off system does not operate.	Headlight dimmer switch circuit	Click here
	Front door courtesy switch circuit	Click here
	IG signal circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Daytime Running Light Control
Symptom	Suspected Area	See page
Daytime running light control does not operate.	Headlight dimmer 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 (Multiplex network body ECU)	Click here

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
	Headlight beam level control actuator circuit	Click here
	Headlight signal circuit	Click here
	Headlight leveling ECU power source circuit	Click here
	Meter circuit plate	Click here
	Headlight leveling ECU assembly	Click here
Headlight beam level control system indicator light does not come on when turning the power switch on (IG).	Indicator circuit	Click here
	Headlight leveling ECU power source circuit	Click here
	Headlight leveling ECU assembly	Click here
	Meter circuit plate	Click here
DTC information can not be detected.	Diagnosis circuit	Click here
DTC information can not be detected.	Headlight leveling ECU assembly	Click here
Initialization can not 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.
When the headlight leveling ECU assembly is replaced, initialization is also necessary.

Manual Headlight Beam Level Control
Symptom	Suspected Area	See page
Headlight beam level control does not operate.	Headlight leveling switch assembly	Click here
	Harness or connector	-
	Headlight leveling motor	Click here