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.
| Symptom | Suspected Area | See page |
|---|---|---|
| Low beam headlights and high beam headlights do not illuminate. | H-LP MAIN fuse | - |
| Headlight dimmer switch circuit | ||
| Headlight relay circuit | ||
| Harness or connector | - | |
| Main body ECU | ||
| Both left and right low beam headlights do not illuminate. | H-LP LH LO fuse and H-LP RH LO fuse | - |
| No. 1 headlight bulb | - | |
| Headlight dimmer switch circuit | ||
| Headlight relay circuit*1 | ||
| Low beam headlight circuit*2 | ||
| Harness or connector | - | |
| Main body ECU | ||
| Low beam headlight on one side does not illuminate. | H-LP LH LO fuse or H-LP RH LO fuse | - |
| No. 1 headlight bulb | - | |
| Harness or connector | - | |
| Both left and right high beam headlights do not illuminate. | H-LP LH HI fuse and H-LP RH HI fuse | - |
| No. 1 headlight bulb | - | |
| Headlight dimmer switch circuit | ||
| Headlight relay circuit*1 | ||
| High beam headlight circuit*2 | ||
| Harness or connector | - | |
| Main body ECU | ||
| High beam headlight on one side does not illuminate. | H-LP LH HI fuse or H-LP RH HI fuse | - |
| No. 1 headlight bulb | - | |
| Harness or connector | - | |
| High beam headlights do not illuminate with "High Flash" function (passing function). | Headlight dimmer switch circuit | |
| Main body ECU | ||
| Clearance lights do not illuminate (taillights are normal). | Clearance light bulb | - |
| Harness or connector | - |
*1: w/o Projector Headlight
*2: w/ Projector Headlight
| Symptom | Suspected Area | See page |
|---|---|---|
| Front fog light on one side does not illuminate. | Front fog light bulb | - |
| Harness or connector | - | |
| Both left and right front fog lights do not illuminate (taillight is normal). | FOG FR fuse | - |
| Headlight dimmer switch circuit | ||
| Front fog light circuit | ||
| Harness or connector | - | |
| Main body ECU |
| Symptom | Suspected Area | See page |
|---|---|---|
| Both left and right tail lights do not illuminate (clearance lights and license plate lights included). | TAIL NO. 2 fuse | - |
| Headlight dimmer switch circuit | ||
| Taillight relay circuit | ||
| Harness or connector | - | |
| Main body ECU | ||
| One taillight (rear combination light assembly) does not illuminate. | Taillight bulb*1 | - |
| Rear combination light assembly*1 | ||
| Rear combination light assembly*2 | ||
| Harness or connector | - | |
| One taillight (rear light assembly) does not illuminate*2 | Rear light assembly | |
| Harness or connector | - | |
| License plate lights do not illuminate (taillight is normal). | License plate light bulb | - |
| License plate light assembly | - | |
| Harness or connector | - |
*1: for Bulb Type Stop Light
*2: for LED Type Stop Light
| Symptom | Suspected Area | See page |
|---|---|---|
| All of stop lights do not illuminate. | STOP fuse | - |
| Stop light switch assembly*1 | ||
| Stop light switch assembly*2 | ||
| Harness or connector | - | |
| Stop light on one side does not illuminate. | Stop light bulb*1 | - |
| Rear combination light assembly*1 | ||
| Rear combination light assembly*2 | ||
| Harness or connector | - | |
| Center stop light does not illuminate. | Center stop light assembly | |
| Harness or connector | - |
*1: for Bulb Type Stop Light
*2: for LED Type Stop Light
| Symptom | Suspected Area | See page |
|---|---|---|
| Rear fog light does not illuminate (taillight is normal). | FOG RR fuse | - |
| Headlight dimmer switch circuit | ||
| Rear fog light circuit | ||
| Rear Light Assembly*1 | ||
| Rear Light Assembly*2 | ||
| Harness or connector | - | |
| Main body ECU |
*1: for Bulb Type Stop Light
*2: for LED Type Stop Light
| Symptom | Suspected Area | See page |
|---|---|---|
| Back-up light on one side does not illuminate. | Back-up light bulb | - |
| Harness or connector | - | |
| Both left and right back-up lights do not illuminate. | Park/neutral position light switch assembly*1 | |
| Back-up light switch assembly*2 | ||
| Back-up light switch assembly*3 | ||
| Back-up light switch assembly*4 | ||
| Back-up light switch assembly*5 | ||
| Harness or connector | - |
*1: for K312
*2: for C551
*3: for EC62
*4: for EC65
*5: for EC69
| Symptom | Suspected Area | See page |
|---|---|---|
| Hazard warning lights do not operate (turn signal lights are normal). | HAZ fuse | - |
| Hazard warning switch circuit | ||
| Harness or connector | - | |
| Combination meter assembly | ||
| Turn signal lights do not operate (hazard warning lights are normal). | Check the DTC (meter / gauge system) | |
| Headlight dimmer switch circuit | ||
| Turn signal lights do not operate in one direction. | Check for DTCs (meter / gauge system) | |
| Headlight dimmer switch circuit | ||
| Front turn signal light on one side does not illuminate. | Check for DTCs (meter / gauge system) | |
| Front turn signal light bulb | - | |
| Harness or connector | - | |
| Side turn signal light on one side does not illuminate. | Check for DTCs (meter / gauge system) | |
| Side turn signal light assembly | - | |
| Outer rear view mirror assembly | - | |
| Harness or connector | - | |
| Rear turn signal light on one side does not illuminate. | Check for DTCs (meter / gauge system) | |
| Rear turn signal light bulb | - | |
| Harness or connector | - |
| Symptom | Suspected Area | See page |
|---|---|---|
| Automatic light control system does not operate. | Check for DTCs | |
| Headlight dimmer switch circuit | ||
| Main body ECU |
| Symptom | Suspected Area | See page |
|---|---|---|
| Light auto turn off system does not operate. | Headlight dimmer switch circuit | |
| Door courtesy switch circuit | ||
| IG signal circuit | ||
| Main body ECU |
| Symptom | Suspected Area | See page |
|---|---|---|
| Battery Saver system does not operate. | Door courtesy switch circuit | |
| IG signal circuit | ||
| Main body ECU |
| Symptom | Suspected Area | See page |
|---|---|---|
| Daytime running light system does not operate. | Headlight dimmer switch circuit | |
| Daytime running light relay circuit | ||
| CAN communication system (w/ Toyota Safety Sense) | ||
| CAN communication system (w/o Toyota Safety Sense) | ||
| ECM (for 1KR-FE) | ||
| ECM (for 2NR-FKE) | ||
| ECM (for 1ND-TV)*1 | ||
| ECM (for 1ND-TV)*2 | ||
| ECM (for 2ZR-FE) | ||
| Main body ECU |
*1: w/ DPF
*2: w/o DPF
| Symptom | Suspected Area | See page |
|---|---|---|
| Follow me home system does not operate. | Headlight dimmer switch circuit | |
| IG signal circuit | ||
| Main body ECU |