Note
If the main body ECU (multiplex network body ECU) is replaced, refer to the Service Bulletin.
As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.*
*: w/ Door Control Battery
When replacing the combination meter assembly, make sure to replace it with a new one.
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.
Inspect the fuses related to this system before inspecting the suspected areas below.
Symptom | Suspected Area | Link |
---|---|---|
Both left and right low beam headlights do not illuminate. | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
Low beam headlight on right side does not illuminate. | Headlight unit RH | |
Headlight unit assembly RH | ||
Headlight ECU sub-assembly RH | ||
Low beam headlight on left side does not illuminate. | Headlight unit LH | |
Headlight unit assembly LH | ||
Headlight ECU sub-assembly LH | ||
Both left and right high beam headlights do not illuminate. | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
High beam headlight on right side does not illuminate. (w/ Adaptive High Beam System) | Headlight unit RH | |
Headlight unit assembly RH | ||
Headlight ECU sub-assembly RH | ||
High beam headlight on left side does not illuminate. (w/ Adaptive High Beam System) | Headlight unit LH | |
Headlight unit assembly LH | ||
Headlight ECU sub-assembly LH | ||
High beam headlight on right side does not illuminate. (w/o Adaptive High Beam System) | High beam headlight circuit | |
High beam headlight on left side does not illuminate. (w/o Adaptive High Beam System) | High beam headlight circuit | |
High beam flash function does not operate (high beam headlights are normal). | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
Low beam and high beam headlight on right side does not illuminate. | Power source circuit | |
Headlight ECU sub-assembly RH | ||
Low beam and high beam headlight on left side does not illuminate. | Power source circuit | |
Headlight ECU sub-assembly LH |
Symptom | Suspected Area | Link |
---|---|---|
Both left and right low beam headlights do not illuminate. | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
Low beam headlight on right side does not illuminate. | Headlight unit RH | |
Headlight unit assembly RH | ||
Headlight ECU sub-assembly RH | ||
Low beam headlight on left side does not illuminate. | Headlight unit LH | |
Headlight unit assembly LH | ||
Headlight ECU sub-assembly LH | ||
Both left and right high beam headlights do not illuminate. | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
High beam headlight on right side does not illuminate. | High beam headlight circuit | |
High beam headlight on left side does not illuminate. | High beam headlight circuit | |
High beam flash function does not operate (high beam headlights are normal). | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
Low beam and high beam headlight on right side does not illuminate. | Power source circuit | |
Headlight ECU sub-assembly RH | ||
Low beam and high beam headlight on left side does not illuminate. | Power source circuit | |
Headlight ECU sub-assembly LH |
Symptom | Suspected Area | Link |
---|---|---|
Both left and right clearance lights do not illuminate. | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
Clearance light on right side does not illuminate. | Daytime running light relay circuit | |
Headlight ECU sub-assembly RH | ||
Clearance light on left side does not illuminate. | Daytime running light relay circuit | |
Headlight ECU sub-assembly LH |
Symptom | Suspected Area | Link |
---|---|---|
Both left and right daytime running lights do not illuminate. | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
Daytime running light on right side does not illuminate. | Daytime running light relay circuit | |
Headlight ECU sub-assembly RH | ||
Daytime running light on left side does not illuminate. | Daytime running light relay circuit | |
Headlight ECU sub-assembly LH | ||
Clearance light and daytime running light on right side does not illuminate. | Power source circuit | |
Daytime running light relay circuit | ||
Headlight ECU sub-assembly RH | ||
Clearance light and daytime running light on left side does not illuminate. | Power source circuit | |
Daytime running light relay circuit | ||
Headlight ECU sub-assembly LH |
Symptom | Suspected Area | Link |
---|---|---|
Both left and right front fog lights do not illuminate (taillight is normal). | Headlight dimmer switch circuit | |
Front fog light circuit | ||
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) | ||
Front fog light on one side does not illuminate. | Front fog light circuit |
Symptom | Suspected Area | Link |
---|---|---|
Rear fog light does not illuminate (taillight is normal). | Headlight dimmer switch circuit | |
Rear fog light circuit | ||
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) |
Symptom | Suspected Area | Link |
---|---|---|
License plate light does not illuminate. | License plate light assembly LH | |
License plate light assembly RH | ||
Harness or connector | - |
Symptom | Suspected Area | Link |
---|---|---|
Taillight (rear combination light assembly) does not illuminate. | Rear combination light socket and wire sub-assembly | |
Rear combination light assembly | ||
Harness or connector | - | |
Instrument panel junction block assembly (for LHD) | ||
Instrument panel junction block assembly (for RHD) | ||
Taillight (rear light assembly) does not illuminate. | Rear light assembly | |
Harness or connector | - | |
Instrument panel junction block assembly (for LHD) | ||
Instrument panel junction block assembly (for RHD) | ||
All of the taillights do not illuminate | Headlight dimmer switch circuit | |
Taillight relay circuit | ||
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) |
Symptom | Suspected Area | Link |
---|---|---|
One side stop light (rear combination light assembly) does not illuminate. | Rear combination light socket and wire sub-assembly | |
Rear combination light assembly | ||
Harness or connector | - | |
One side stop light (rear light assembly) does not illuminate. | Rear light assembly | |
Harness or connector | - | |
Center stop light does not illuminate. | Center stop light assembly | |
Harness or connector | - | |
All of the stop lights do not operate. | Harness or connector | - |
Stop light switch assembly | ||
Stop light control ECU assembly (for LHD) | ||
Stop light control ECU assembly (for RHD) |
Symptom | Suspected Area | Link |
---|---|---|
All of the back-up lights do not operate. | Harness or connector | - |
Instrument panel junction block assembly (for LHD) [BKUP LP relay] | ||
Instrument panel junction block assembly (for RHD) [BKUP LP relay] | ||
ECM (for 3ZR-FAE) | ||
ECM (for 8AR-FTS) | ||
Back-up light on one side does not illuminate. | Rear light assembly | |
Harness or connector | - |
Symptom | Suspected Area | Link |
---|---|---|
Back-up light does not illuminate. | Harness or connector | - |
Rear light assembly | ||
Instrument panel junction block assembly (for LHD) [BKUP LP relay] | ||
Instrument panel junction block assembly (for RHD) [BKUP LP relay] | ||
ECM (for 3ZR-FAE) | ||
ECM (for 8AR-FTS) |
Symptom | Suspected Area | Link |
---|---|---|
No turn signal lights operate (hazard warning lights are normal). | Turn signal switch circuit | |
Combination meter assembly | ||
One of the turn signal lights does not operate. | Meter/gauge system |
Symptom | Suspected Area | Link |
---|---|---|
Both left and right cornering lights do not illuminate. | Headlight dimmer switch circuit | |
Combination meter assembly | ||
Cornering light on right side does not illuminate. | Cornering light circuit | |
Headlight ECU sub-assembly RH | ||
Cornering light on left side does not illuminate. | Cornering light circuit | |
Headlight ECU sub-assembly LH |
Symptom | Suspected Area | Link |
---|---|---|
Hazard warning lights do not operate (turn signal lights are normal). | Harness or connector | - |
Hazard warning switch circuit | ||
Combination meter assembly | ||
Emergency brake signal (hazard warning light blink) does not operate (w/ Emergency Brake Signal) | CAN communication system | |
Vehicle stability control system | ||
Combination meter assembly |
Symptom | Suspected Area | Link |
---|---|---|
Automatic light control system does not operate. | Headlight dimmer switch circuit | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) |
Symptom | Suspected Area | Link |
---|---|---|
Light auto turn-off system does not operate. | Headlight dimmer switch circuit | |
Door courtesy switch circuit | ||
IG signal circuit | ||
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) |
Symptom | Suspected Area | Link |
---|---|---|
Follow me home system does not operate. | IG signal circuit | |
Headlight dimmer switch circuit | ||
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) |
Symptom | Suspected Area | Link |
---|---|---|
Welcome light illumination control does not operate. | Check customize parameters (Light up Clearance Lights at Door Unlock Function) | |
Main body ECU (multiplex network body ECU) (for LHD) | ||
Main body ECU (multiplex network body ECU) (for RHD) |