Toyota 4Runner: System Description

Toyota 4Runner Service Manual / Vehicle Interior / Door Lock / Power Door Lock Control System / System Description

SYSTEM DESCRIPTION

1. POWER DOOR LOCK CONTROL SYSTEM DESCRIPTION

(a) The power door lock system locks/unlocks all the doors.

The driver and front passenger side door control switches send lock/unlock request signals to the main body ECU (multiplex network body ECU). Then, the main body ECU (multiplex network body ECU) sends these request signals to the door lock motors in each door to lock/unlock all the doors at once in response to the inputs.

Operating the driver door lock using a mechanical key sends request signals to lock or unlock the doors to the main body ECU (multiplex network body ECU).

2. FUNCTION OF MAIN COMPONENTS

Component	Function
Multiplex network master switch assembly	Driver side door control switch on the master switch locks or unlocks all doors.
Door control switch assembly	Front passenger side door control switch on the door control switch locks or unlocks all doors.
Door courtesy light switch assembly	Located on each door. Detects the door status (open or closed) and outputs data to the main body ECU (multiplex network body ECU). Turns on when the door is opened and turns off when the door is closed.
Front door lock assembly LH	Built-in motor locks or unlocks the door. Built-in door control switch (key-linked) detects the door key cylinder operation status (locked or unlocked) and outputs a signal to the main body ECU (multiplex network body ECU). Built-in position switch detects door the status (locked or unlocked) and outputs a signal to the main body ECU (multiplex network body ECU). This switch turns off when the door is locked and turns on when the door is unlocked.
Front door lock assembly RH Rear door lock assembly LH Rear door lock assembly RH	Built-in motor locks or unlocks the door. Built-in position switch detects the door status (locked or unlocked) and outputs a signal to the main body ECU (multiplex network body ECU). This switch turns off when the door is locked and turns on when the door is unlocked.
Back door lock assembly	Built-in motor opens the door. Performs the back door open operation according to the door position determined by the main body ECU (multiplex network body ECU).
Main body ECU (multiplex network body ECU)	Detects the vehicle condition based on the signals from each switch, the vehicle speed signal, airbag operation signal, etc. and controls the power door lock system. Sends lock/unlock signals to each door lock assembly to operate the door lock motors.
Combination meter assembly	Calculates the vehicle speed based on the signal from the skid control ECU and sends the vehicle speed information to the main body ECU (multiplex network body ECU) via CAN communication.

3. SYSTEM FUNCTION

(a) This system is controlled by the main body ECU (multiplex network body ECU). The main body ECU (multiplex network body ECU) outputs signals to each door lock motor. The door lock control system of the vehicle has the following functions:

Function	Outline
Manual lock and unlock function	This function locks or unlocks all doors according to the door lock control switch operation.
Key-linked lock and unlock function	This function, which is linked with the mechanical key cylinder, locks or unlocks all doors when a lock or unlock operation is performed.
Key lock-in prevention function	When the key is in the vehicle, this function prevents the door lock operation performed with the lock switch on the outer handle from locking the door.
Key-linked 2-step unlock function	Unlocks only the driver door when the key cylinder is turned once and unlocks the other doors when the key cylinder is turned twice.
Shift-linked automatic door lock function	When the conditions listed below are met consecutively, this function causes all doors to be automatically locked. All doors are closed. The shift lever is moved out of P.
Shift-linked automatic door unlock function	When the conditions listed below are met consecutively, this function causes all doors to be automatically unlocked. The ignition switch is ON. The shift lever is moved to P from any position other than P.
Speed-sensitive automatic door lock function*	When the conditions listed below are met consecutively, this function causes all doors to be automatically locked. Vehicle speed is higher than approximately 20 km/h (12 mph). All doors are closed. Any of the doors is unlocked.
Driver door-linked automatic door unlock*	All doors are unlocked automatically when the driver door is opened within 10 seconds after the ignition switch is turned from ON to off.

*: Default setting is OFF.

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