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Problem Symptoms Table

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
  1. HEADLAMP AND TAIL LAMP 
    PROBLEM SYMPTOMS TABLE - HEADLIGHT AND TAILLIGHT SYSTEM

    Symptom Suspected Area
    Only one headlamp comes on.
    1. Bulb
    2. HEAD LH fuse (LWR, UPR)
    3. HEAD RH fuse (LWR, UPR)
    4. Harness or connector
    Headlamp does not light up. -
    "Hi-Beam" does not light (All).
    1. Headlamp dimmer switch
    2. Harness or connector
    "Hl-Beam" does not light (One side).
    1. Bulb
    2. Harness or connector
    "Flash" does not light.
    1. Headlamp Dimmer Switch
    2. Turn signal flasher relay
    3. Harness or connector
    Headlamp is dark.
    1. Bulb
    2. Harness or connector
    Only one tail lamp light up.
    1. Bulb
    2. Harness or connector
    Tail lamp does not light up. (Headlamp is normal) -
    Tail lamp does not light up. (Headlamp does not light)
    1. Light Control Switch
    2. Harness or connector
    Rear combination light does not light up.
    1. Bulb
    2. Harness or connector
    Headlamp does not light up with engine running and light control switch is in OFF (Daytime running light operation).
    1. Turn signal flasher and DRL relay
    2. Generator L terminal
    3. Parking brake switch
    4. Multiplex network body ECU
    5. Harness or connector
  2. AUTOMATIC LIGHT CONTROL SYSTEM 
    PROBLEM SYMPTOMS TABLE - AUTOMATIC LIGHT CONTROL SYSTEM

    Symptom Suspected Area
    Automatic light control system does not operate -
  3. LIGHT AUTO CUT SYSTEM 
    PROBLEM SYMPTOMS TABLE - LIGHT AUTO CUT SYSTEM

    Symptom Suspected Area
    Light auto turn off system does not operate. -
    Headlamp and tail lamp do not come on.
    1. Multiplex network body ECU
    2. Harness or connector
    Headlamp and taillight stay on.
    1. Multiplex network body ECU
    2. Harness or connector
  4. FOG LAMP SYSTEM 
    PROBLEM SYMPTOMS TABLE - FOG LAMP SYSTEM

    Symptom Suspected Area
    Front fog lamp does not light up with light control SW HEAD (Headlamp is normal).
    1. FOG Fuse
    2. FOG relay
    3. Fog lamp switch
    4. Harness or connector
    Only one front fog lamp does not light up.
    1. Bulb
    2. Harness or connector
  5. TURN SIGNAL AND HAZARD WARNING SYSTEM 
    PROBLEM SYMPTOMS TABLE - TURN SIGNAL AND HAZARD WARNING SYSTEM

    Symptom Suspected Area
    "Hazard" and "Turn" do not light up.
    1. IG1 Fuse
    2. Ignition switch
    3. Turn signal flasher
    4. Harness or connector
    Hazard warning light does not light up. (Turn is normal)
    1. Hazard warning switch
    2. Harness or connector
    Turn signal does not light up. (Hazard is normal)
    1. Turn signal switch
    2. Harness or connector
    Turn signal does not light up in one direction.
    1. Turn signal switch
    2. Harness or connector
    Only one bulb does not light up.
    1. Bulb
    2. Harness or connector
  6. ILLUMINATED ENTRY SYSTEM 
    PROBLEM SYMPTOMS TABLE - ILLUMINATION LIGHT SYSTEM

    Symptom Suspected Area
    Room lamp assy No.1 does not light up. -
    Room lamp assy No.1 does not go off. -
    Courtesy lamp does not light up.
    1. Courtesy lamp
    2. Courtesy lamp switch
    3. Harness or connector
    4. Driver side junction block assy
    Courtesy lamp does not go off.
    1. Courtesy lamp switch
    2. Harness or connector
    3. Courtesy lamp
    4. Driver side junction block assy
    Side step lamp does not light up.
    1. Side step lamp
    2. Courtesy lamp switch
    3. Harness or connector
    4. Multiplex network body ECU
    Side step lamp does not go off.
    1. Courtesy lamp switch
    2. Harness or connector
    3. Side step lamp
    4. Multiplex network body ECU
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