System Description

2007 Toyota Highlander Hybrid, FWDSECTION System Description
  1. GENERAL 

    The defogger system's thin heater wires are attached to the inside of the rear window and defog the window surface quickly. The indicator light illuminates while the system is operating. The system automatically turns off after approximately 15 minutes.

    HINT:

    The rear window defogger is linked with the mirror defogger.

  2. FUNCTION OF MAIN COMPONENT 
    MAIN COMPONENT FUNCTION CHART

    Component Outline
    RR-DEF Relay Receives rear defogger activation request signals from A/C amplifier assembly (A/C ECU) and supplies power to rear window defogger.
    Rear Window Defogger Receives power from DEFOG relay and heats defogger wire.
    w/ Deicer
    Deicer Relay
    Receives front deicer activation request signals from A/C amplifier assembly (A/C ECU) and supplies power to front window deicer.
    w/ Deicer
    Front Window Deicer
    Receives power from DEICER relay and heats deicer wire.
  3. DESCRIPTION 
    MAIN COMPONENT DESCRIPTION CHART

    Function Outline
    Defogs the rear window surface
    • Receives rear defogger activation request signals from A/C amplifier assembly (A/C ECU) and supplies power to rear window defogger.
    • Receives power from DEFOG relay and heats defogger wire.
    Defogs the front window surface
    • Receives front deicer activation request signals from A/C amplifier assembly (A/C ECU) and supplies power to front window deicer.
    • Receives power from DEICER relay and heats deicer wire.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.