Power Window Control System (Diagnostics & Symptom Tests): Overview Lexus IS II facelift 2

SYSTEM DESCRIPTION [08/2012 - ]

1. POWER WINDOW CONTROL SYSTEM DESCRIPTION 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.
2. 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.
3. 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.

DESCRIPTION

When the engine switch is on (IG), the multiplex network master switch assembly sends remote up/down signals to each power window regulator motor assembly via the LIN communication line.

Scheme 6

When the engine is running or the engine switch is on (IG), the power window regulator motor assembly (for driver side) is operated by the multiplex network master switch assembly. The power window regulator motor assembly (for driver side) has motor, regulator, and ECU functions.

HINT

If the pulse sensor built into the power window regulator motor assembly (for driver side) malfunctions, the power window control system enters fail-safe mode. The remote up/down and auto up/down functions cannot be operated during fail-safe mode. However, the power window can be closed by holding the multiplex network master switch assembly in the auto up position, and opened manually by pushing down the multiplex network master switch assembly.

Scheme 7

When the engine is running or the engine switch is on (IG), the power window regulator motor assembly (for front passenger side) is operated by the power window regulator switch assembly (for front passenger side). The power window regulator motor assembly (for front passenger side) has motor, regulator, and ECU functions.

HINT

If the pulse sensor built into the power window regulator motor assembly (for front passenger side) malfunctions, the power window control system enters fail-safe mode. The remote up/down and auto up/down functions cannot be operated during fail-safe mode. However, the power window can be closed by holding the power window regulator switch assembly (for front passenger side) in the auto up position, and opened manually by pushing down the power window regulator switch assembly (for front passenger side).

Scheme 8

When the engine is running or the engine switch is on (IG), the power window regulator motor assembly (for rear LH side) is operated by the power window regulator switch assembly (for rear LH side). The power window regulator motor assembly (for rear LH side) has motor, regulator, and ECU functions.

HINT

If the pulse sensor built into the power window regulator motor assembly (for rear LH side) malfunctions, the power window control system enters fail-safe mode. The remote up/down and auto up/down functions cannot be operated during fail-safe mode. However, the power window can be closed by holding the power window regulator switch assembly (for rear LH side) in the auto up position, and opened manually by pushing down the power window regulator switch assembly (for rear LH side).

Scheme 9

When the engine is running or the engine switch is on (IG), the power window regulator motor assembly (for rear RH side) is operated by the power window regulator switch assembly (for rear RH side). The power window regulator motor assembly (for rear RH side) has motor, regulator, and ECU functions.

HINT

If the pulse sensor built into the power window regulator motor assembly (for rear RH side) malfunctions, the power window control system enters fail-safe mode. The remote up/down and auto up/down functions cannot be operated during fail-safe mode. However, the power window can be closed by holding the power window regulator switch assembly (for rear RH side) in the auto up position, and opened manually by pushing down the power window regulator switch assembly (for rear RH side).

Scheme 10

If the manual up/down function can be performed but the auto up/down function cannot, then the fail-safe mode may be functioning.

If the power window initialization. Refer to INITIALIZATION [08/2012 - ] has not been performed, the auto up/down function will not operate.

Scheme 11

If the manual up/down function can be performed but the auto up/down function cannot, the fail-safe mode may be functioning.

If the power window initialization. Refer to INITIALIZATION [08/2012 - ] has not been performed, the auto up/down function will not operate.

Scheme 12

If the manual up/down function can be performed but the auto up/down function cannot, the fail-safe mode may be functioning.

If the power window initialization. Refer to INITIALIZATION [08/2012 - ] has not been performed, the auto up/down function will not operate.

Scheme 13

If the manual up/down function can be performed but the auto up/down function cannot, the fail-safe mode may be functioning.

If the power window initialization. Refer to INITIALIZATION [08/2012 - ] has not been performed, the auto up/down function will not operate.

Scheme 14

1. When a key switch is pushed: 1) the door control receiver assembly receives the key signal; 2) the door control receiver assembly sends a signal to the certification ECU (smart key ECU assembly); 3) the multiplex network master switch assembly sends the operation permission signal to the power window regulator motor assembly; and 4) the power window regulator motor assemblies are activated.
2. When the driver door key cylinder (key linked switch) is turned: 1) the door lock motor receives the signal; 2) the multiplex network master switch assembly sends the signal to the power window regulator motor assembly; and 3) the power window regulator motor assemblies are activated.

1. When the front doors are closed, each power window regulator motor assembly can control its power window operation for approximately 45 seconds after the engine switch is turned from on (IG) to off by receiving operation permission signals from the main body ECU RH (cowl side junction block RH).
2. However, when approximately 45 seconds have elapsed, or the driver side door or front passenger side door is opened within approximately 45 seconds of the engine switch being turned off, the power window regulator motor assembly disables manual operation.
3. During an auto operation, when 45 seconds have passed and key-off operation is prohibited, the window operation will not stop until the auto operation is completed.

If a door glass or a power window regulator motor assembly does not operate smoothly, the jam protection function may be triggered automatically, resulting in the auto up function being unable to fully close the window.

HINT

This symptom may occur for any of the windows.

This symptom may occur for any of the windows.

The jam protection function operates within a specified range during the manual up or auto up operation.