Toyota Tundra Service Manual: System Description

Toyota Tundra Service Manual / Vehicle Interior / Door Lock / Key Reminder Warning System / System Description

SYSTEM DESCRIPTION

1. KEY REMINDER WARNING SYSTEM DESCRIPTION

(a) When the driver side door is opened with the ignition key in the ACC or LOCK position, this system causes a buzzer to sound in order to warn the driver that the ignition key has not been removed.

2. FUNCTION OF MAIN COMPONENT

Component

Function

Front Door Courtesy Switch LH

Detects front door status (open or closed) and outputs signal to main body ECU

Unlock Warning Switch

Detects if key is inserted into ignition key cylinder or not and outputs signal to main body ECU

Combination Meter

Receives buzzer request signal from main body ECU after main body ECU receives ignition switch signal and front door courtesy light switch signal, and actuates inner circuit to sound built-in buzzer intermittently
    Problem Symptoms Table

    System Diagram

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    Toyota Tundra Service Manual

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