System Description

WARNING: This page is about a different car, the 2009 Lexus IS 350 and 2009 Lexus IS 250. However, it is still accessible from the selected car via links, so may be relevant.

POWER WINDOW CONTROL SYSTEM DESCRIPTION
1. The power window control system controls the power window operation using the power window regulator motors. The main controls of this system are the multiplex network master switch assembly, which is mounted on the driver side door, and the power window regulator switches, which are mounted on the front passenger side door and rear doors. Operating a window switch results in electrical power being transmitted to the corresponding power window regulator motor.

FUNCTION OF MAIN COMPONENTS

The power window control system consists of the following components:

Component	Outline
Multiplex Network Master Switch Assembly	Controls power window operation for all seats. When lock switch is set to lock position, window operation will be possible only for driver side power window.
Power Window Regulator Switch Assembly Front Passenger Side Rear LH Side Rear RH Side	Located on front passenger side door and rear doors. Each switch controls window operation for its respective window.
Power Window Regulator Motor Assembly	Receives switch signals and changes signals into motor activation. As a result, window position changes. Uses Hall-IC in regulator motor with ECU to detect window position and jamming.

SYSTEM FUNCTION

The power window control system has the following functions:

Function	Outline
Manual up-and-down function	Function that causes the window to go up while the power window switch is being pulled halfway up and to go down while pushed halfway down. The window stops as soon as the switch is released.
All door auto up-and-down function	Function that enables windows of all doors to be fully opened or closed by one full pull or push of the multiplex network master switch assembly or power window regulator switch assembly.
Window lock function	Function where front passenger side power window switch and rear power window switch operations are disabled when the window lock switch is pressed. The front passenger side power window switch and rear power window switches can be operated when the window lock switch is pressed again.
Jam protection function	Function that automatically stops power window and moves it downward if a foreign object gets jammed in door window during auto up operation.
Remote control function	Function that allows the multiplex network master switch assembly to control manual and auto up-and-down operations of the front passenger door window and rear door windows.
Key-off operation function	Function that makes it possible to operate all power windows for approximately 45 sec. after the engine switch is turned off when the driver side door or front passenger side door has not been opened. If 45 sec. have passed or a front door is opened while the auto function is operating, the window operation stops.
Key-linked open and close	When the key is not inside the vehicle, the driver side door is locked, and the key inserted into the driver side door key cylinder is turned and maintained in the lock position for 2.3 seconds or more, the multiplex network master switch assembly activates the power window regulator motor assemblies to close all power windows while the key is turned. Similarly, when the driver door is unlocked, turning and maintaining the driver side door key in the unlock position for 2.3 seconds or more will cause all power windows to open.
Wireless transmitter-linked open	When the certification ECU (smart key ECU assembly) receives UNLOCK signal from the electrical key transmitter for 3 seconds or more, the multiplex network master switch assembly sends operation permission signal to the power window ECU in each power window regulator motor assembly. Each power window ECU then controls the motor to open the window.
Diagnosis	Function that allows diagnosis of the power window control system if any of the power window ECUs (built into each power window regulator motor assembly) detect a malfunction in the system. If a malfunction is detected, the power window ECU will illuminate the LEDs on the multiplex network master switch assembly and the respective power window regulator switch assembly to inform the driver and passenger of the malfunction.
Fail-safe	A fail-safe function to disable a part of power window functions if the pulse sensor in the power window motor has a malfunction. Auto up-and-down function and remote control function are disabled.