Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM1000000018H8L
Model Year Start: 2018 Model: Sienna Prod Date Range: [11/2017 -           ]
Title: LIGHTING (EXT): LIGHTING SYSTEM: PROBLEM SYMPTOMS TABLE; 2018 - 2020 MY Sienna [11/2017 -        ]

PROBLEM SYMPTOMS TABLE

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

Symptom

Suspected Area

See page

One low beam headlight does not illuminate.

Bulb (for Halogen Headlight)

-

Discharge headlight bulb (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HIGH INTENSITY DISCHARGE HEADLIGHT BULB: ON-VEHICLE INSPECTION

Headlight Relay (H-LP Relay)

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): RELAY: ON-VEHICLE INSPECTION

Harness or connector

-

Light control ECU (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: COMPONENTS

Both left and right low beam headlights do not illuminate.

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

Headlight relay circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Headlight Relay Circuit

Headlight Relay (H-LP Relay)

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): RELAY: ON-VEHICLE INSPECTION

Harness or connector

-

Instrument panel junction block assembly

-

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

One high beam headlight does not illuminate.

H-LP LH HI fuse or H-LP RH HI fuse

-

Bulb

-

Running light relay (w/ Daytime Running Light System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): DAYTIME RUNNING LIGHT RELAY(for Bulb Type): COMPONENTS

Harness or connector

-

Both left and right high beam headlights do not illuminate.

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

High beam headlight circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Headlight (HI-BEAM) Circuit

Running light relay (w/ Daytime Running Light System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): DAYTIME RUNNING LIGHT RELAY(for Bulb Type): COMPONENTS

Headlight dimmer relay (DIM Relay) (w/o Daytime Running Light System)

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): RELAY: ON-VEHICLE INSPECTION

Instrument panel junction block assembly

-

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

"High Flash" (passing function) headlight does not illuminate (high beam headlights are normal).

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

Instrument panel junction block assembly

-

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

Discharge headlight bulb flickers.

Harness or connector

-

Discharge headlight bulb (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HIGH INTENSITY DISCHARGE HEADLIGHT BULB: ON-VEHICLE INSPECTION

Light control ECU (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: COMPONENTS

Discharge headlight bulb is dark.

Harness or connector

-

Discharge headlight bulb (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HIGH INTENSITY DISCHARGE HEADLIGHT BULB: ON-VEHICLE INSPECTION

Light control ECU (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: COMPONENTS

Discharge headlight bulb does not come on at intervals.

Harness or connector

-

Discharge headlight bulb (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HIGH INTENSITY DISCHARGE HEADLIGHT BULB: ON-VEHICLE INSPECTION

Light control ECU (w/ HID Headlight System)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HEADLIGHT ASSEMBLY: COMPONENTS

One front parking/side marker light does not illuminate.

Bulb (for DRL Bulb Type)

-

Headlight assembly (for DRL LED Type)

-

Harness or connector

-

One rear taillight does not illuminate.

Bulb (for Bulb Stop Light Type)

-

Rear light assembly (for LED Stop Light Type)

-

Harness or connector

-

One rear side marker does not illuminate.

Rear combination light assembly

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY: COMPONENTS

Harness or connector

-

One license plate light does not illuminate.

Bulb

-

Harness or connector

-

All of the lights (rear taillights, front parking/side marker lights, license plate lights and rear side marker lights) do not illuminate.

TAIL fuse

-

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

Taillight relay circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Taillight Relay Circuit

Instrument panel junction block assembly

-

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

Stop Light

Symptom

Suspected Area

See page

One side stop light does not illuminate.

Rear combination light assembly (for LED Type Stop Light)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): REAR COMBINATION LIGHT ASSEMBLY: COMPONENTS

Bulb (for Bulb Type Stop Light)

-

Harness or connector

-

High mounted stop light does not illuminate.

High mounted stop light assembly

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): HIGH MOUNTED STOP LIGHT ASSEMBLY: COMPONENTS

Harness or connector

-

All of lights do not illuminate.

STOP fuse

-

ECU-IG NO. 1 fuse (w/ Dynamic Radar Cruise Control)

-

Stop light switch assembly (for Bulb Type Stop Light)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): STOP LIGHT SWITCH: INSPECTION

Stop light switch assembly (for LED Type Stop Light)

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): STOP LIGHT SWITCH: ON-VEHICLE INSPECTION

STOP LP relay (w/ Dynamic Radar Cruise Control)

-

Harness or connector

-

Front Fog Light

Symptom

Suspected Area

See page

One side front fog light does not illuminate.

Bulb

-

Harness or connector

-

Both left and right front fog lights do not illuminate (taillight is normal).

TAIL fuse or FOG FR fuse

-

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

Front fog light circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Front Fog Light Circuit

Front fog light relay

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): RELAY: ON-VEHICLE INSPECTION

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

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.

GAUGE NO. 1 fuse

-

Park/neutral position switch (for UA80F)

2017 - 2020 MY Sienna [08/2016 -        ]; UA80F (AUTOMATIC TRANSMISSION / TRANSAXLE): PARK / NEUTRAL POSITION SWITCH: INSPECTION

Park/neutral position switch (for UA80E)

2017 - 2020 MY Sienna [08/2016 -        ]; UA80E (AUTOMATIC TRANSMISSION / TRANSAXLE): PARK / NEUTRAL POSITION SWITCH: INSPECTION

Harness or connector

-

Turn Signal and Hazard Warning Light

Symptom

Suspected Area

See page

Hazard warning lights do not operate (turn signal lights are normal).

HAZ fuse

-

Hazard warning switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Hazard Warning Switch Circuit

Combination meter assembly

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

Turn signal lights do not operate (hazard warning lights are normal).

Check the DTC (meter / gauge system)

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: DTC CHECK / CLEAR

Turn signal switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Turn Signal Switch Circuit

Combination meter assembly

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

Turn signal lights do not operate in one direction.

Check for DTCs (meter / gauge system)

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: DTC CHECK / CLEAR

Turn signal switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Turn Signal Switch Circuit

Combination meter assembly

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: COMBINATION METER: REMOVAL

Front turn signal light on one side does not illuminate.

Check for DTCs (meter / gauge system)

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: DTC CHECK / CLEAR

Bulb

-

Harness or connector

-

Side turn signal light on one side does not illuminate.

Check for DTCs (meter / gauge system)

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: DTC CHECK / CLEAR

Bulb

-

Side turn signal light assembly (w/ HID Headlight System)

-

Outer mirror control ECU (w/ Seat Position Memory)

-

Outer rear view mirror assembly (w/ Seat Position Memory)

-

Harness or connector

-

Rear turn signal light on one side does not illuminate.

Check for DTCs (meter / gauge system)

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: DTC CHECK / CLEAR

Bulb

-

Harness or connector

-

Automatic Light Control System

Symptom

Suspected Area

See page

Automatic light control system does not operate.

Check DTCs

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: DTC CHECK / CLEAR

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

IG signal circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (INT): LIGHTING SYSTEM: IG Signal Circuit

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

Light Auto Turn-off System

Symptom

Suspected Area

See page

Light auto turn-off system does not operate.

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

Door courtesy switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (INT): LIGHTING SYSTEM: Door Courtesy Switch Circuit

IG signal circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (INT): LIGHTING SYSTEM: IG Signal Circuit

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

Daytime Running Light System

Symptom

Suspected Area

See page

Daytime running light system does not operate.

Check CAN communication system

2018 - 2020 MY Sienna [11/2017 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING

Daytime running light relay circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Daytime Running Light Relay Circuit

Light control switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Light Control Switch Circuit

IG signal circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (INT): LIGHTING SYSTEM: IG Signal Circuit

Parking brake switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Parking Brake Switch Circuit

High beam headlight circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Headlight (HI-BEAM) Circuit

Meter / gauge system

2016 - 2020 MY Sienna [12/2015 -        ]; METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS

Automatic High Beam System (w/ Automatic High Beam System)

Symptom

Suspected Area

See page

Automatic high beam system does not operate or operation indicator does not illuminate.

Check automatic high beam indicator light

2018 - 2020 MY Sienna [11/2017 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Automatic High Beam System does not Operate or Operation Indicator does not Illuminate

Check Data List (Auto H Beam STS)

Check Active Test (Automatic High Beam Indicator)

Check automatic high beam main switch

Harness or connector

Door Mirror Foot Light

Symptom

Suspected Area

See page

One door mirror foot light does not illuminate.

Door mirror foot light assembly

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): DOOR MIRROR FOOT LIGHT: INSPECTION

Door mirror foot light circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Door Mirror Foot Light Circuit

Outer mirror control ECU assembly

2016 - 2020 MY Sienna [12/2015 -        ]; MIRROR (EXT): OUTER MIRROR CONTROL ECU: COMPONENTS

Both left and right door mirror foot lights do not illuminate.

Power door lock control system

2016 - 2020 MY Sienna [12/2015 -        ]; DOOR LOCK: POWER DOOR LOCK CONTROL SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING

Wireless door lock control system

2016 - 2020 MY Sienna [12/2015 -        ]; DOOR LOCK: WIRELESS DOOR LOCK CONTROL SYSTEM(w/ Smart Key System): HOW TO PROCEED WITH TROUBLESHOOTING

Door mirror foot light circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (EXT): LIGHTING SYSTEM: Door Mirror Foot Light Circuit

Door courtesy switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (INT): LIGHTING SYSTEM: Door Courtesy Switch Circuit

Door unlock detection switch circuit

2016 - 2020 MY Sienna [12/2015 -        ]; LIGHTING (INT): LIGHTING SYSTEM: Door Unlock Detection Switch Circuit

IG signal circuit

2017 - 2020 MY Sienna [08/2016 -        ]; LIGHTING (INT): LIGHTING SYSTEM: IG Signal Circuit

Main body ECU

2016 - 2020 MY Sienna [12/2015 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: COMPONENTS