LIGHTING SYSTEM > PROBLEM SYMPTOMS TABLE

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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 (except LED 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
-
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.
Headlight unit
Click here
Main body ECU (Multiplex network body ECU)
Click here
Harness or connector
-
One taillight does not illuminate.
Rear combination light assembly
Click here
Harness or connector
-
One license plate light does not illuminate.
License plate light assembly
Click here
Harness or connector
-
All of the lights (taillights, parking lights and license plate lights) do not illuminate.
(TAIL fuse is normal.)
Headlight dimmer switch circuit
Click here
Taillight relay circuit
Click here
Main body ECU (Multiplex network body ECU)
Click here
All of the lights (taillights, parking lights and license plate lights) do not illuminate.
(Though TAIL fuse has been replaced the fuse brakes again.)
License plate light assembly
Click here
Rear combination light assembly
Click here
Headlight unit
Click here
Harness or connector
-

Headlight and Taillight (for LED Headlight) 
Symptom
Suspected Area
See page
One low beam headlight does not illuminate.
Check DTCs
Click here
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
One high beam headlight does not illuminate.
H-LP LH HI fuse or H-LP RH HI fuse
-
Bulb
-
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.
Headlight unit
Click here
Main body ECU (Multiplex network body ECU)
Click here
Harness or connector
-
One rear taillight does not illuminate.
Rear combination light assembly
Click here
Harness or connector
-
One license plate light does not illuminate.
License plate light assembly
Click here
Harness or connector
-
All of the lights (rear taillights, parking lights and license plate lights) do not illuminate.
(TAIL fuse is normal.)
Headlight dimmer switch circuit
Click here
Taillight relay circuit
Click here
Main body ECU (Multiplex network body ECU)
Click here
All of the lights (taillights, parking lights and license plate lights) do not illuminate.
(Though TAIL fuse has been replaced the fuse brakes again.)
License plate light assembly
Click here
Rear combination light assembly
Click here
Headlight unit
Click here
Harness or connector
-

Stop Light 
Symptom
Suspected Area
See page
One side 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 the stop lights do not illuminate.
STOP fuse
-
Stop light switch assembly
Click here
Stop light control relay
Click here
Harness or connector
-
All of the stop lights do not turn off.
Stop light switch assembly
Click here
Stop light control relay
Click here
Brake booster with master cylinder (for LHD)*1
Click here
Brake booster with master cylinder (for RHD)*1
Click here
Harness or connector
-
  1. *1: The stop lights may always come on due to abnormality of the brake booster with master cylinder.

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 (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

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.
Back-up light circuit
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
-
Side turn signal light does not operate.
Side turn signal light assembly
Click here
Harness or connector
-
Outer mirror control ECU assembly*1
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 fuse
-
TURN & 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
-
  1. *1: w/ Seat Memory Switch

Hazard Warning Light 
Symptom
Suspected Area
See page
Hazard warning lights do not operate.
TURN & HAZ fuse
-
Hazard warning switch circuit
Click here
Turn signal flasher assembly
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 (w/ Light Reminder) 
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
Door courtesy switch circuit
Click here
IG signal circuit
Click here
Main body ECU (Multiplex network body ECU)
Click here

Light Auto Turn-off System (w/o Light Reminder) 
Symptom
Suspected Area
See page
Light auto turn-off system does not operate.
Headlight dimmer switch circuit
Click here
Door courtesy switch circuit
Click here
IG signal circuit
Click here
Main body ECU (Multiplex network body ECU)
Click here

Daytime Running Light System 
Symptom
Suspected Area
See page
Daytime running light system does not operate.
CAN communication system
Click here
Headlight dimmer switch circuit
Click here
IG signal circuit
Click here
Daytime running light relay circuit
Click here
Main body ECU (Multiplex network body ECU)
Click here

Door Mirror Foot Light (w/ Seat Memory Position) 
Symptom
Suspected Area
See page
One door mirror foot light does not illuminate.
Bulb
-
Door mirror foot light circuit
Click here
Outer mirror control ECU assembly
Click here
Both left and right door mirror foot light 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 mirror foot light circuit
Click here
Door unlock detection switch circuit
Click here
Main body ECU (Multiplex network body ECU)
Click here

Door Mirror Foot Light (w/o Seat Memory Position) 
Symptom
Suspected Area
See page
One door mirror foot light does not illuminate.
Bulb
-
Outer rear view mirror assembly
Click here
Harness or connector
-
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
Click here
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 (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 light circuit
Click here
Headlight leveling ECU assembly (for LHD)
Click here
Headlight leveling ECU assembly (for RHD)
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 (for LHD)
Click here
Headlight leveling ECU assembly (for RHD)
Click here
Headlight beam level control system indicator light does not come on when turning the power switch on (IG).
Indicator light circuit
Click here
Headlight leveling ECU assembly (for LHD)
Click here
Headlight leveling ECU assembly (for RHD)
Click here
Combination meter assembly
Click here
DTC information can not be detected.
Diagnosis circuit
Click here
Headlight leveling ECU assembly (for LHD)
Click here
Headlight leveling ECU assembly (for RHD)
Click here
Initialization can not be performed.
Check DTCs
Click here
LVL terminal circuit
Click here
Headlight leveling ECU assembly (for LHD)
Click here
Headlight leveling ECU assembly (for RHD)
Click here

NOTICE:
  1. 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.
  2. When the headlight leveling ECU assembly is replaced, initialization is also necessary.