Operation CHARM: Car repair manuals for everyone.

Windows: Description and Operation

POWER WINDOWS

DESCRIPTION
The power window system allows each of the door windows to be raised and lowered electrically by actuating a switch on the trim panel of each respective door. A master switch on the driver side front door trim panel allows the driver to raise or lower each of the passenger door windows and to lock out the individual switches on the passenger doors from operation. The power window system receives battery feed through a circuit breaker in the Junction Block (JB), only when the ignition switch is in the ON position.

The power window system includes the power window switches on each door trim panel, circuit breaker, door modules and the power window motors inside each door.

The window motors are replaced with the window regulator assembly. If the window motors require replacement, the window regulator must be replaced.

OPERATION

POWER WINDOW SWITCH
The power windows are controlled by a window/lock switch on the trim panel of each front door. Switches in the driver door window/lock switch allows the driver to control the passenger windows.

The power window switch for the driver side front door window has a second detent position beyond the normal Down position that provides an automatic one-touch window down feature.

Some vehicles may be equipped with an express closing feature (front windows only). During an express closing, anytime an obstacle is detected in the way of the glass, the motor will stop and reverse travel to avoid pinching an occupant's fingers, etc. Modules in the doors are programmed to compare the position of the glass to the amount of current that is being used to drive up the glass.

The system also includes various features to manage the perceived forces on the glass as it travels up. If the express closing calibration is lost, the system will self-calibrate itself after the windows are moved up and down two cycles.

The power window switches control the battery and ground feeds to the power window motors. All of the passenger door power window switches receive their battery and ground feeds through the circuitry of the window/lock switch. When the power window lockout switch is in the Lock position, the battery feed for the individual passenger door power window switches is interrupted.

POWER WINDOW MOTOR
A permanent magnet reversible motor moves the window regulator through an integral gearbox mechanism. A positive and negative battery connection to the two motor terminals will cause the motor to rotate in one direction. Reversing the current through these same two connections will cause the motor to rotate in the opposite direction. In addition, each power window motor is equipped with an integral self-resetting circuit breaker to protect the motor from overloads.