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Problem Symptoms Table

WARNING: This page is about a different car, the 2008 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Use the table below to help determine the cause of the problem symptom. 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 tail light system 

HEADLIGHT AND TAIL LIGHT SYSTEM

Symptom Suspected Area See
"Low beam" does not comes on (One side). 1. HEAD LL fuse, HEAD RL fuse HEADLIGHT RELAY CIRCUIT 
2. Bulb HEADLIGHT RELAY CIRCUIT 
3. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
4. Headlight relay circuit HEADLIGHT RELAY CIRCUIT 
5. Instrument panel junction block TERMINALS OF ECU 
"Low beam" does not come on (Both sides). 1. HEAD LL fuse, HEAD RL fuse HEADLIGHT RELAY CIRCUIT 
2. Bulb HEADLIGHT RELAY CIRCUIT 
3. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
4. Headlight relay circuit HEADLIGHT RELAY CIRCUIT 
5. Instrument panel junction block TERMINALS OF ECU 
"High beam" does not come on (One side). 1. HEAD LH fuse, HEAD RH fuse HEADLIGHT (HI-BEAM) CIRCUIT 
2. HEAD RL fuse HEADLIGHT RELAY CIRCUIT 
3. Bulb HEADLIGHT (HI-BEAM) CIRCUIT 
4. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
5. Headlight (Hi-beam) circuit HEADLIGHT (HI-BEAM) CIRCUIT 
6. Instrument panel junction block TERMINALS OF ECU 
"High beam" does not come on (Both sides). 1. HEAD LH fuse, HEAD RH fuse HEADLIGHT (HI-BEAM) CIRCUIT 
2. HEAD RL fuse HEADLIGHT RELAY CIRCUIT 
3. Bulb HEADLIGHT (HI-BEAM) CIRCUIT 
4. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
5. Headlight (Hi-beam) circuit HEADLIGHT (HI-BEAM) CIRCUIT 
6. Instrument panel junction block TERMINALS OF ECU 
"Low beam" and "High beam" do not come on (One side). 1. HEAD LL fuse, HEAD RL fuse HEADLIGHT RELAY CIRCUIT 
2. HEAD LH fuse, HEAD RH fuse HEADLIGHT (HI-BEAM) CIRCUIT 
3. Bulb (high) HEADLIGHT (HI-BEAM) CIRCUIT 
4. Bulb (low) HEADLIGHT RELAY CIRCUIT 
5. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
6. Headlight relay circuit HEADLIGHT RELAY CIRCUIT 
7. Headlight (Hi-beam) circuit HEADLIGHT (HI-BEAM) CIRCUIT 
8. Instrument panel junction block TERMINALS OF ECU 
"Low beam" and "High beam" do not come on (Both sides). 1. HEAD LL fuse, HEAD RL fuse HEADLIGHT RELAY CIRCUIT 
2. HEAD LH fuse, HEAD RH fuse HEADLIGHT (HI-BEAM) CIRCUIT 
3. Bulb (high) HEADLIGHT (HI-BEAM) CIRCUIT 
4. Bulb (low) HEADLIGHT RELAY CIRCUIT 
5. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
6. Headlight relay circuit HEADLIGHT RELAY CIRCUIT 
7. Headlight (Hi-beam) circuit HEADLIGHT (HI-BEAM) CIRCUIT 
8. Instrument panel junction block TERMINALS OF ECU 
"Flash" does not come on (Low beam and Hi-beam are normal). 1. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
2. Instrument panel junction block TERMINALS OF ECU 
Headlight is dark. 1. Bulb -
2. Wire harness -
Taillight does not come on (All). 1. TAIL fuse TAILLIGHT RELAY CIRCUIT 
2. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
3. Taillight relay circuit TAILLIGHT RELAY CIRCUIT 
4. Instrument panel junction block TERMINALS OF ECU 
Only one front side marker light comes on. 1. Bulb TAILLIGHT RELAY CIRCUIT 
2. Wire harness TAILLIGHT RELAY CIRCUIT 
Only one taillight comes on. 1. Rear combination light REAR COMBINATION LIGHT ASSEMBLY 
2. Wire harness TAILLIGHT RELAY CIRCUIT 
Only one rear side marker light comes on. 1. Bulb TAILLIGHT RELAY CIRCUIT 
2. Wire harness TAILLIGHT RELAY CIRCUIT 
Daytime running light system does not operate. 1. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
2. CAN communication line ECM COMMUNICATION STOP MODE
3. Parking brake switch circuit  
4. Daytime running light relay circuit DRL RELAY CIRCUIT 
5. Instrument panel junction block TERMINALS OF ECU 

Light auto turn off system 

LIGHT AUTO TURN OFF SYSTEM

Symptom Suspected Area See
Light auto turn off system does not operate. 1. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
2. Ignition switch  
3. Door courtesy switch circuit DOOR COURTESY SWITCH CIRCUIT 
4. Instrument panel junction block TERMINALS OF ECU 

Fog light system 

FOG LIGHT SYSTEM

Symptom Suspected Area See
Front fog light does not come on with light control switch in TAIL or HEAD position. 1. FF FOG fuse FRONT FOG LIGHT CIRCUIT 
2. Front fog light relay FRONT FOG LIGHT CIRCUIT 
3. Light control switch circuit LIGHT CONTROL SWITCH CIRCUIT 
4. Front fog light circuit FRONT FOG LIGHT CIRCUIT 
5. Instrument panel junction block TERMINALS OF ECU 
Only one front fog light does not come on. 1. Bulb FRONT FOG LIGHT CIRCUIT 
2. Wire harness FRONT FOG LIGHT CIRCUIT 

Turn signal and hazard warning system 

TURN SIGNAL AND HAZARD WARNING SYSTEM

Symptom Suspected Area See
"Hazard" and "Turn" do not come on. 1. HAZ fuse HAZARD WARNING SWITCH CIRCUIT 
2. ECU-IG2 fuse TURN SIGNAL LIGHT CIRCUIT 
3. Ignition switch  
4. Turn signal flasher relay TURN SIGNAL FLASHER ASSEMBLY 
5. Wire harness -
Hazard warning light does not come on (Turn is normal). 1. Hazard warning switch HAZARD WARNING SWITCH CIRCUIT 
2. Wire harness HAZARD WARNING SWITCH CIRCUIT 
Turn signal does not come on (Hazard is normal). 1. Headlight dimmer switch (turn signal switch) TURN SIGNAL LIGHT CIRCUIT 
2. Wire harness TURN SIGNAL LIGHT CIRCUIT 
Turn signal does not come on in one direction. 1. Headlight dimmer switch (turn signal switch) TURN SIGNAL LIGHT CIRCUIT 
2. Wire harness TURN SIGNAL LIGHT CIRCUIT 
Only one bulb does not come on. 1. Bulb TURN SIGNAL LIGHT CIRCUIT 
2. Wire harness TURN SIGNAL LIGHT CIRCUIT 

Stop light system 

STOP LIGHT SYSTEM

Symptom Suspected Area See
Stop light does not operate (All). 1. STOP fuse STOP LIGHT SWITCH CIRCUIT 
2. BRK relay BRK RELAY 
3. Stop light switch  
4. Wire harness STOP LIGHT SWITCH CIRCUIT 
Only one stop light does not operate. 1. Rear combination light REAR COMBINATION LIGHT ASSEMBLY 
2. Wire harness STOP LIGHT SWITCH CIRCUIT 

Illuminated entry system 

ILLUMINATED ENTRY SYSTEM

Symptom Suspected Area See
Illuminated entry of multiplex network body ECU control does not operate (All). 1. Ignition switch REMOVAL (2AZ-FE) or REMOVAL (2GR-FE)
2. Door lock position circuit DOOR LOCK POSITION CIRCUIT 
3. Door courtesy switch circuit DOOR COURTESY SWITCH CIRCUIT 
4. Illumination circuit FOOTWELL LIGHT CIRCUIT 
5. Instrument panel junction block TERMINALS OF ECU 

Foot light system 

FOOT LIGHT SYSTEM

Symptom Suspected Area See
Step light of body ECU control does not operate. 1. Ignition switch REMOVAL (2AZ-FE) or REMOVAL (2GR-FE)
2. Door lock position switch DOOR LOCK POSITION CIRCUIT 
3. Door courtesy switch circuit DOOR COURTESY SWITCH CIRCUIT 
4. Footwell light circuit FOOTWELL LIGHT CIRCUIT 
5. Instrument panel junction block TERMINALS OF ECU 

Others 

OTHERS

Symptom Suspected Area See
Vanity light does not operate. 1. Bulb VANITY LIGHT 
2. Vanity light switch VANITY LIGHT 
3. Wire harness -
Back-up light does not come on (All). 1. GAUGE 1 fuse BACK-UP LIGHT CIRCUIT 
2. Park / neutral position switch INSPECTION
3. Wire harness BACK-UP LIGHT CIRCUIT 
Back door courtesy light does not come on. 1. Bulb LUGGAGE ROOM LIGHT 
2. DOME fuse -
3. Back door courtesy switch BACK DOOR COURTESY SWITCH 
4. Wire harness -
Center console illumination does not come on. 1. Center console light FRONT CONSOLE ILLUMINATION 
2. Wire harness -