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Problem Symptoms Table

Headlight system: 

PROBLEM SYMPTOMS CHART - HEADLIGHT SYSTEM

Symptom Suspected area See
One side LO-beam headlight does not illuminate 1. H-LP L LWR fuse or H-LP R LWR fuse -
2. Bulb -
3. Light control ECU -
4. Wire harness -
Both left and right LO-beam headlights do not illuminate 1. HEAD LP relay HEADLIGHT RELAY 
2. Headlight relay circuit HEADLIGHT RELAY CIRCUIT 
3. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
4. Headlight signal circuit HEADLIGHT SIGNAL CIRCUIT 
5. Front controller (Engine room No. 2 R/B) -
6. Main body ECU RH (Cowl side J/B RH) -
Without HID headlight: One side Hl-beam headlight does not illuminate 1. Bulb -
2. Wire harness -
With HID headlight: One side Hl-beam headlight does not illuminate 1. Bulb -
2. Wire harness -
3. Front controller (Engine room No. 2 R/B) -
Both left and right Hl-beam headlights do not illuminate 1. H-LP UPR fuse -
2. Headlight (HI-BEAM) circuit HEADLIGHT (HI-BEAM) CIRCUIT 
3. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
4. Headlight signal circuit HEADLIGHT SIGNAL CIRCUIT 
5. Front controller (Engine room No. 2 R/B) -
6. Main body ECU RH (Cowl side J/B RH) -
"Flash" headlight does not illuminate 1. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
2. Main body ECU RH (Cowl side J/B RH) -
3. Front controller (Engine room No. 2 R/B) -
When headlight dimmer switch is moved to Hl-beam position, LO-beam of discharge headlights remains on, but illumination area of discharge headlights is not increased. (Bi-function does not work.) 1. Headlight solenoid circuit HEADLIGHT SOLENOID CIRCUIT 
2. Front controller (Engine room No. 2 R/B) -
3. Headlight assembly HEADLIGHT ASSEMBLY 

Daytime running light system: 

PROBLEM SYMPTOMS CHART - DAYTIME RUNNING LIGHT SYSTEM

Symptom Suspected area See
Daytime running light system does not operate 1. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
2. Parking brake switch INSPECTION
3. Front controller (Engine room No. 2 R/B) -
4. Main body ECU RH (Cowl side J/B RH) -

Taillight system: 

PROBLEM SYMPTOMS CHART - TAILLIGHT SYSTEM

Symptom Suspected area See
Parking light does not operate 1. Bulb -
2. Wire harness -
3. Headlight assembly HEADLIGHT ASSEMBLY 
One side taillight does not illuminate 1. Rear combination light assembly REAR COMBINATION LIGHT ASSEMBLY 
2. Wire harness -
Taillight system does not operate (Taillights, front side marker lights, parking lights, license plate lights, and side marker lights do not illuminate) 1. FR TAIL fuse -
2. Taillight circuit TAILLIGHT CIRCUIT 
3. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
4. Front controller (Engine room No. 2 R/B) -
5. Main body ECU LH (Cowl side J/B LH) -

Side marker system: 

PROBLEM SYMPTOMS CHART - SIDE MARKER SYSTEM

Symptom Suspected area See
Front side marker light does not illuminate 1. Headlight assembly -
Rear side marker light does not illuminate 1. Rear combination light assembly REAR COMBINATION LIGHT ASSEMBLY 

Stop light system: 

PROBLEM SYMPTOMS CHART - STOP LIGHT SYSTEM

Symptom Suspected area See
Stop light system does not operate 1. STOP SW fuse -
2. Stop light switch STOP LIGHT SWITCH 
3. BRK-LP relay STOP LIGHT CONTROL RELAY (FOR AUTOMATIC TRANSMISSION)
4. Rear combination light REAR COMBINATION LIGHT ASSEMBLY 
5. Wire harness -
One side stop light does not illuminate 1. Rear combination light REAR COMBINATION LIGHT ASSEMBLY 
2. Wire harness -
High mounted stop light does not illuminate 1. High mounted stop light assembly HIGH MOUNTED STOP LIGHT ASSEMBLY 
2. Wire harness -

Front fog light system: 

PROBLEM SYMPTOMS CHART - FRONT FOG LIGHT SYSTEM

Symptom Suspected area See
One side fog light does not illuminate 1. Bulb -
2. Front fog light circuit FRONT FOG LIGHT CIRCUIT 
3. Fog light assembly FOG LIGHT ASSEMBLY 
Both left and right fog lights do not illuminate 1. FR FOG fuse -
2. FR FOG relay -
3. Front fog light circuit FRONT FOG LIGHT CIRCUIT 
4. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
5. Front controller (Engine room No. 2 R/B) -
6. Main body ECU RH (Cowl side J/B RH) -

Turn signal light system: 

PROBLEM SYMPTOMS CHART - TURN SIGNAL LIGHT SYSTEM

Symptom Suspected area See
Hazard warning light does not operate 1. TURN-HAZ fuse -
2. LH-IG fuse -
3. Turn signal flasher TURN SIGNAL FLASHER ASSEMBLY 
4. Hazard warning switch HAZARD WARNING SWITCH 
5. Hazard warning switch circuit HAZARD WARNING SWITCH CIRCUIT 
6. Turn signal light circuit TURN SIGNAL LIGHT CIRCUIT 
7. Main body ECU RH (Cowl side J/B RH) -
One side turn signal light does not operate 1. Bulb -
2. Turn signal flasher TURN SIGNAL FLASHER ASSEMBLY 
3. Turn signal light circuit TURN SIGNAL LIGHT CIRCUIT 
4. Headlight assembly HEADLIGHT ASSEMBLY 
5. Rear combination light assembly REAR COMBINATION LIGHT ASSEMBLY 
6. Main body ECU LH (Cowl side J/B LH) -
All turn signal lights do not flash 1. TURN-HAZ fuse -
2. LH-IG fuse -
3. Turn signal light circuit TURN SIGNAL LIGHT CIRCUIT 
4. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
5. Hazard warning switch HAZARD WARNING SWITCH 
6. Main body ECU LH (Cowl side J/B LH) -
All turn signal lights do not flash at the correct speed 1. Bulb -
2. Turn signal flasher TURN SIGNAL FLASHER ASSEMBLY 
3. Side turn signal light -
4. Headlight assembly HEADLIGHT ASSEMBLY 
5. Rear combination light assembly REAR COMBINATION LIGHT ASSEMBLY 
6. Wire harness -

Back-up light system: 

PROBLEM SYMPTOMS CHART - BACK-UP LIGHT SYSTEM

Symptom Suspected area See
One side back-up light does not illuminate 1. Bulb -
2. Wire harness -
Both left and right back-up lights do not illuminate 1. LH-IG fuse -
2. Back-up light switch (for M/T) REAR COMBINATION LIGHT ASSEMBLY 
3. Park/Neutral position switch (for A/T) REMOVAL
4. Wire harness -

License plate light system: 

PROBLEM SYMPTOMS CHART - LICENSE PLATE LIGHT SYSTEM

Symptom Suspected area See
One side license plate light does not illuminate 1. License plate light LICENSE PLATE LIGHT ASSEMBLY 
2. Wire harness -
Both left and right license plate lights do not illuminate 1. TAIL fuse -
2. License plate light LICENSE PLATE LIGHT ASSEMBLY 
3. Wire harness -

Interior light system: 

PROBLEM SYMPTOMS CHART - INTERIOR LIGHT SYSTEM

Symptom Suspected area See
Front personal lights do not illuminate 1. Bulb -
2. DOME fuse -
3. Overhead J/B (Personal light) PERSONAL LIGHT ASSEMBLY 
4. Wire harness -
Rear personal lights do not illuminate 1. DOME fuse -
2. Rear room light assembly (Personal light) REAR ROOM LIGHT ASSEMBLY 
3. Wire harness -
Seat illumination does not illuminate 1. Bulb -
2. DOME fuse -
3. Seat illumination circuit SEAT ILLUMINATION CIRCUIT 
4. Interior light switch signal circuit INTERIOR LIGHT SWITCH SIGNAL CIRCUIT 
5. Rear room light assembly REAR ROOM LIGHT ASSEMBLY 
6. Overhead J/B (Interior light switch) PERSONAL LIGHT ASSEMBLY 
7. Main body ECU RH (Cowl side J/B RH) -
8. Main body ECU LH (Cowl side J/B LH) -
Door courtesy lights do not illuminate 1. DOME fuse -
2. Door courtesy light -
3. Door courtesy switch FRONT DOOR COURTESY SWITCH 
4. Door courtesy switch circuit DOOR COURTESY SWITCH CIRCUIT 
5. Interior light switch signal circuit INTERIOR LIGHT SWITCH SIGNAL CIRCUIT 
6. Overhead J/B (Interior light switch) PERSONAL LIGHT ASSEMBLY 
7. Main body ECU RH (Cowl side J/B RH) -
Scuff plate lights do not illuminate 1. DOME fuse -
2. Scuff plate light SCUFF PLATE LIGHT 
3. Scuff plate light circuit SCUFF PLATE LIGHT CIRCUIT 
4. Interior light switch signal circuit INTERIOR LIGHT SWITCH SIGNAL CIRCUIT 
5. Overhead J/B (Interior light switch) PERSONAL LIGHT ASSEMBLY 
6. Main body ECU LH (Cowl side J/B LH) -
7. Main body ECU RH (Cowl side J/B RH) -
Shift illumination does not illuminate 1. DOME fuse -
2. Shift illumination circuit SHIFT ILLUMINATION CIRCUIT 
3. Overhead J/B -
4. Main body ECU LH (Cowl side J/B LH) -
5. Main body ECU RH (Cowl side J/B RH) -
Glove box light does not illuminate 1. ACC fuse -
2. Glove box light GLOVE BOX LIGHT 
3. Wire harness -
Foot well lights do not illuminate 1. DOME fuse -
2. Footwell light FOOTWELL LIGHT 
3. Footwell light circuit FOOTWELL LIGHT CIRCUIT 
4. Main body ECU RH (Cowl side J/B RH) -
Register illumination does not illuminate 1. PANEL fuse -
2. Register illumination REGISTER ILLUMINATION 
3. Wire harness -
Console box light does not illuminate 1. ACC fuse -
2. Console box light CONSOLE BOX LIGHT 
3. Wire harness -
Luggage compartment room light does not illuminate 1. Bulb -
2. DOME fuse -
3. Luggage compartment room light LUGGAGE COMPARTMENT ROOM LIGHT 
4. Wire harness -

Others: 

PROBLEM SYMPTOMS CHART

Symptom Suspected area See
Vanity light does not illuminate 1. Bulb -
2. Visor assembly -
3. Wire harness -
Battery saving function does not operate 1. Main body ECU LH (Cowl side J/B LH) -
2. Main body ECU RH (Cowl side J/B RH) -
Door mirror foot lights do not illuminate 1. DOME fuse -
2. Door mirror foot light DOOR MIRROR FOOT LIGHT 
3. Door mirror foot light circuit DOOR MIRROR FOOT LIGHT CIRCUIT 
4. Interior light switch signal circuit LIGHT CONTROL SWITCH CIRCUIT 
5. Overhead J/B (Interior light switch) PERSONAL LIGHT ASSEMBLY 
6. Main body ECU LH (Cowl side J/B LH) -
7. Main body ECU RH (Cowl side J/B RH) -

AFS 

PROBLEM SYMPTOMS CHART - AFS

Symptom Suspected area See
AFS does not operate (*1) 1. AFS ECU power source circuit AFS ECU POWER SOURCE CIRCUIT 
2. AFS ECU -
3. Combination meter assembly COMBINATION METER
Only one swivel motor is not initialized (*1) 1. Headlight assembly or swivel motor stuck (*2) DTC B2412 HEADLIGHT SWIVEL MOTOR LH MALFUNCTION; DTC B2413 HEADLIGHT SWIVEL MOTOR RH MALFUNCTION 
2. Headlight swivel motor malfunction DTC B2412 HEADLIGHT SWIVEL MOTOR LH MALFUNCTION; DTC B2413 HEADLIGHT SWIVEL MOTOR RH MALFUNCTION 
3. AFS ECU -
Only swivel control does not operate or malfunctions 1. AFS ECU switch status (*3) AFS OFF SWITCH CIRCUIT 
2. Vehicle speed sensor malfunction DTC B2415 VEHICLE SPEED SENSOR MALFUNCTION 
3. BEAN communication malfunction MULTIPLEX COMMUNICATION SYSTEM
4. Headlight swivel motor malfunction DTC B2412 HEADLIGHT SWIVEL MOTOR LH MALFUNCTION; DTC B2413 HEADLIGHT SWIVEL MOTOR RH MALFUNCTION 
5. AFS ECU -
Swivel control and leveling control do not operate 1. Height control sensor malfunction DTC B2416 HEIGHT CONTROL SENSOR MALFUNCTION 
2. Headlight swivel motor malfunction DTC B2412 HEADLIGHT SWIVEL MOTOR LH MALFUNCTION; DTC B2413 HEADLIGHT SWIVEL MOTOR RH MALFUNCTION 
3. AFS ECU -
AFS OFF indicator light does not come on 1. AFS OFF switch circuit AFS OFF SWITCH CIRCUIT 
2. AFS ECU -
3. Combination meter assembly COMBINATION METER
HINT:
  • *1: When the AFS indicator light does not come on or blink despite the symptom being occurring, check the battery voltage.
  • *2: Check if the headlight swivel motor turns smoothly by hand. If the motor does not turn, replace it with a new one. If the motor still does not turn, replace the headlight assembly with a new one.
  • *3: Before beginning diagnosis, check that the AFS setting is ON.
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