Toyota 4Runner: System Description

Toyota 4Runner 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 while the ignition switch is ACC or off and the key is in the ignition key cylinder, this system causes a buzzer to sound in order to warn the driver that the key has not been removed.

(b) The key reminder warning buzzer volume and the amount of time that the buzzer sounds can be changed using the Techstream.

2. FUNCTION OF MAIN COMPONENT

Component	Function
Front door courtesy light switch assembly LH	Detects the driver side door status (open or closed) and outputs a signal to the main body ECU (multiplex network body ECU).
Unlock warning switch assembly	Detects if the key is inserted into the ignition key cylinder or not and outputs a signal to the main body ECU (multiplex network body ECU).
Combination meter assembly	Receives a buzzer request signal from the main body ECU (multiplex network body ECU) after the main body ECU (multiplex network body ECU) receives an ignition switch signal, unlock warning switch signal and front door courtesy light switch LH signal, and activates the inner circuit to sound the built-in buzzer intermittently.

How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT HINT: Use the following procedures to troubleshoot the key reminder warning system. *: Use the Techstream. PROCEDURE 1. VEHICLE ...

Operation Check

OPERATION CHECK 1. CHECK KEY REMINDER WARNING SYSTEM (a) Check that the key reminder warning buzzer sounds. (1) With the driver side door closed, insert the key into the ignition key cylinder and ...

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