LIGHTING SYSTEM PROBLEM SYMPTOMS TABLE

Note

If the headlight light control ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the headlight light control ECU sub-assembly LH.

Click here
Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.

Tech Tips

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
Symptom	Suspected Area	Link
Left low beam headlight does not illuminate	Headlight housing assembly LH	Click here
	Headlight unit assembly LH	Click here
	Headlight light control ECU sub-assembly LH	Click here
Right low beam headlight does not illuminate	Headlight housing assembly RH	Click here
	Headlight unit assembly RH	Click here
	Headlight light control ECU sub-assembly RH	Click here
Both left and right low beam headlights do not illuminate	Headlight dimmer switch circuit	Click here
Both left and right low beam headlights do not illuminate	Main body ECU (Multiplex network body ECU)	Click here
Left high beam headlight does not illuminate	Headlight housing assembly LH	Click here
	Headlight unit assembly LH	Click here
	Headlight light control ECU sub-assembly LH	Click here
Right high beam headlight does not illuminate	Headlight housing assembly RH	Click here
	Headlight unit assembly RH	Click here
	Headlight light control ECU sub-assembly RH	Click here
Both left and right high beam headlights do not illuminate	Headlight dimmer switch circuit	Click here
Both left and right high beam headlights do not illuminate	Main body ECU (Multiplex network body ECU)	Click here
High Flash (passing function) does not operate (high beam headlights are normal)	Headlight dimmer switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
Left low beam headlight and high beam headlight do not illuminate	Power source circuit	Click here
	Headlight light control ECU sub-assembly LH	Click here
Right low beam headlight and high beam headlight do not illuminate	Power source circuit	Click here
	Headlight light control ECU sub-assembly RH	Click here

Clearance Light
Symptom	Suspected Area	Link
Left clearance light does not illuminate	Daytime running light relay circuit	Click here
Left clearance light does not illuminate	Headlight light control ECU sub-assembly LH	Click here
Right clearance light does not illuminate	Daytime running light relay circuit	Click here
Right clearance light does not illuminate	Headlight light control ECU sub-assembly RH	Click here
Both left and right clearance lights do not illuminate	Headlight dimmer switch circuit	Click here
Both left and right clearance lights do not illuminate	Main body ECU (Multiplex network body ECU)	Click here

Daytime Running Light
Symptom	Suspected Area	Link
Left daytime running light does not illuminate	Daytime running light relay circuit	Click here
Left daytime running light does not illuminate	Headlight light control ECU sub-assembly LH	Click here
Right daytime running light does not illuminate	Daytime running light relay circuit	Click here
Right daytime running light does not illuminate	Headlight light control ECU sub-assembly RH	Click here
Both left and right daytime running lights do not illuminate	CAN communication system	Click here
	Parking brake switch circuit	Click here
	Headlight dimmer switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Taillight
Symptom	Suspected Area	Link
One side taillight (rear combination light assembly) does not illuminate	Rear combination light lens and body	Click here
	Rear combination light socket and wire sub-assembly	Click here
	Harness or connector	-
One taillight (rear light assembly) does not illuminate	Rear light lens and body	Click here
	Rear light socket and wire sub-assembly	Click here
	Harness or connector	-

License Plate Light
Symptom	Suspected Area	Link
One license plate light does not illuminate	License plate light assembly	Click here
One license plate light does not illuminate	Harness or connector	-
Both left and right license plate lights do not illuminate	Harness or connector	-

Stop Light
Symptom	Suspected Area	Link
One side stop light (rear combination light assembly) does not illuminate	Rear combination light lens and body	Click here
	Rear combination light socket and wire sub-assembly	Click here
	Harness or connector	-
One side stop light (rear light assembly) does not illuminate (Stop light in rear light assembly)	Rear light lens and body	Click here
	Rear light socket and wire sub-assembly	Click here
	Harness or connector	-
Center stop light does not illuminate	Center stop light assembly	Click here
Center stop light does not illuminate	Harness or connector	-
All of the stop lights do not illuminate	STOP fuse	-
	Stop light switch assembly	Click here
	Semiconductor pwr integration ECU	Click here
	Harness or connector	-

Rear Fog Light (w/ Rear Fog Light)
Symptom	Suspected Area	Link
Rear fog light does not illuminate (taillights are normal)	Rear light lens and body	Click here
	Rear light socket and wire sub-assembly	Click here
	Headlight dimmer switch circuit	Click here
	Rear fog light circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Back-up Light (w/o Rear Fog Light)
Symptom	Suspected Area	Link
One back-up light does not illuminate	Back-up light bulb	Click here
	Rear light socket and wire sub-assembly	Click here
	Harness or connector	-
Both left and right back-up lights do not illuminate	BKUP LP fuse	-
	Park/neutral position switch assembly	Click here
	Instrument panel junction block assembly	Click here
	Harness or connector	-

Back-up Light (w/ Rear Fog Light)
Symptom	Suspected Area	Link
Back-up light does not illuminate	BKUP LP fuse	-
	Back-up light bulb	Click here
	Rear light socket and wire sub-assembly	Click here
	Park/neutral position switch assembly	Click here
	Instrument panel junction block assembly	Click here
	Harness or connector	-

Turn Signal Light
Symptom	Suspected Area	Link
One turn signal light does not operate (except side turn signal lights)	Clearance light assembly (for Front Side)	Click here
	Turn signal light bulb (for Rear Side)	Click here
	Rear combination light socket and wire sub-assembly	Click here
	Harness or connector	-
One side turn signal light does not operate	Side turn signal light assembly	Click here
	Outer rear view mirror assembly	Click here
	Harness or connector	-
Turn signal lights do not operate in one direction	Turn signal switch circuit	Click here
	Windshield wiper switch assembly	Click here
	Meter/gauge system	Click here
All turn signal lights do not operate	Turn signal switch circuit	Click here
	Windshield wiper switch assembly	Click here
	Combination meter assembly	Click here
All turn signal lights do not flash at the correct speed	Combination meter assembly	Click here

Hazard Warning Signal Light
Symptom	Suspected Area	Link
Hazard warning signal lights do not operate	Hazard warning switch circuit	Click here
Hazard warning signal lights do not operate	Combination meter assembly	Click here

Automatic Light Control System
Symptom	Suspected Area	Link
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
Symptom	Suspected Area	Link
Light auto turn-off system does not operate	Headlight dimmer switch circuit	Click here
	IG signal circuit	Click here
	Door courtesy switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Outside Handle Foot Light Control
Symptom	Suspected Area	Link
Both left and right outside handle foot lights do not illuminate	CAN communication system	Click here
	Power door lock control system	Click here
	Wireless door lock control system	Click here
	Entry and start system (for Entry Function)	Click here
	Door unlock detection switch circuit	Click here
	Outside handle foot light circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here
One outside handle foot light does not illuminate	Front door outside handle assembly	Click here
One outside handle foot light does not illuminate	Harness or connector	-

Welcome Light Illumination Control
Symptom	Suspected Area	Link
Welcome light illumination control does not operate	Wireless door lock control system	Click here
	Headlight dimmer switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here

Follow Me Home System (w/ Follow Me Home System)
Symptom	Suspected Area	Link
Follow me home system does not operate	IG signal circuit	Click here
	Headlight dimmer switch circuit	Click here
	Main body ECU (Multiplex network body ECU)	Click here