Toyota Tundra Service Manual: System Description

Toyota Tundra Service Manual / Vehicle Interior / Window / Glass / Window Defogger System / System Description

SYSTEM DESCRIPTION

1. GENERAL

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

2. FUNCTION OF MAIN COMPONENT

Component

Outline

Air conditioning control assembly (rear window defogger switch)

Located on air conditioning control assembly , detects rear window defogger switch operation and transmits signals to air conditioning amplifier through LIN communication line

Defogger relay

Receives rear window defogger activation request signals from air conditioning amplifier and supplies power to rear window defogger

Back window glass (defogger wire)

Receives power from defogger relay and heats back window glass (defogger wire)

3. DESCRIPTION

Function

Outline

Rear window defogger
  • Defogger relay receives rear window defogger activation request signals from air conditioning amplifier and defogs rear window surface
  • Receives power from defogger relay and heats back window glass (defogger wire)
    Rear Window Defogger System does not Operate

    System Diagram

    See More:

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    DESCRIPTION The ECM operates the air pump heater (AI HTR) relay which causes the air pump heater (AI HTR) to operate. DTC No. DTC Detection Condition Trouble Area P144C Open or short in the air pump heater (AI HTR) relay circuit for 5 seconds (1 trip detection logic). Open or short in air pump heate ...

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