Windows: Description and Operation

CIRCUIT OPERATION
A Permanent Magnet (PM) motor operates each of the power windows. Each Window Motor raises or lowers the glass when voltage is supplied to it. The direction in which the motor turns depends on the polarity of the supplied voltage. The Window Switches control the supply voltage polarity.

Each motor is protected by a built-in solid state circuit breaker. If a Window Switch is held too long with the window obstructed or after the window is fully up or down, the circuit breaker opens the circuit. The circuit breaker resets automatically when voltage is removed from the motor.

The LH Door Switch Assembly controls both motors and both Express Down Window Modules. The RH Door Switch Assembly only controls the RH Window Motor and the RH Express Down Window Module.

Power
When the Ignition Switch is in RUN, or when the RAP feature is activated, battery voltage is applied through CKT 76 to the LH Door Switch Assembly terminal C2/A, RH Door Switch Assembly terminal C3/A and the LH and RH Express Down Window Modules terminal A.

LH Window Operation
When the LH window UP switch is pressed voltage is applied from LH Door Switch Assembly terminal C2/A through the UP contacts to terminal C1/D, through CKT 164 to terminal A of the LH Window Motor. The motor is grounded to G301 through CKT 965, the LH Express Down Window Module, CKT 165, the DN contacts to terminal C2/B of the LH Door Switch Assembly, and CKT 804. The motor runs to drive the window up.

If the DN switch is held for less than 0.3 seconds, voltage is applied to the LH Window Motor through the same CKTs but in the opposite direction. Voltage is now applied through the DN contacts, and the motor is grounded through the UP contacts in the LH Door Switch Assembly. The motor runs briefly to drive the window down. If the DN switch is held for more than 0.3 seconds the express down feature will be activated (see Express Down Window Operation).

RH Window Operation
The RH Window Motor can be operated from both the LH and RH Door Switch Assemblies. When the RH window UP switch in the RH Door Switch Assembly is pressed voltage is applied from switch assembly terminal C3/A through the UP contacts to terminal C2/B, through CKT 666 to terminal A of the RH Window Motor. The motor is grounded to G301 through CKT 966, the RH Express Down Window Module, CKT 667, the DN contacts of the RH Door Switch Assembly, CKT 167, the DN contacts of the LH Door Switch Assembly and CKT 804. The motor runs to drive the window up.

If the DN switch is held for less than 0.3 seconds, voltage is applied to the RH Window Motor through the same CKTs but in the opposite direction. Voltage is now applied through the DN contacts in the RH Door Switch Assembly, and the motor is grounded through the UP contacts in the RH and LH Door Switch Assemblies. The motor runs briefly to drive the window down. If the DN switch is held for more than 0.3 seconds the express down feature will be activated (see Express Down Window Operation).

When the RH window is operated from the LH Door Switch Assembly, the motor works the same way but the voltage is now supplied by the LH Door Switch Assembly through the RH Door Switch Assembly UP or DN contact.

Express Down Window Operation
When a DN switch is held for more than 0.3 seconds the Timer and Control Unit, within the Express Down Window Module, detects this at the down input terminal. The Relay Control Switch closes completing the Relay coil ground circuit through the UP contact in the Door Switch Assembly, energizing the relay. The Relay contacts close applying voltage at the Express Down Window Module terminal A to terminal D, through CKT 965 or 966 to the Window Motor. The motor runs to drive the window down.

When the window is fully down the motor stall current is detected at the current sense input of the Timer and Control Unit. The Relay Control Switch is opened, deenergizing the Relay and disconnecting power to the Window Motor. If the motor stall current has not been detected 10-30 seconds after the down input was detected, the Timer and Control Unit will open the Relay Control Switch, de-energizing the Relay and disconnecting power to the Window Motor.

The express down feature can be halted if either the DN or UP Switch is pressed. If the DN Switch is pressed voltage is applied to terminal B of the Express Down Window Module and is detected by the Timer and Control Unit at the down input terminal. The Timer and Control Unit opens the Relay Control Switch, de-energizing the Relay and disconnecting power to the Window Motor. The window will stop moving down. If the UP Switch is pressed voltage is applied to terminal C of the Express Down Window Module and is detected by the Timer and Control Unit at the up-stop input terminal. The Timer and Control Unit opens the Relay Control Switch, de-energizing the Relay and disconnecting power to the Window Motor. The window will stop moving down and will start moving up if the UP Switch is held. If the power input at terminal A of the Express Down Window Module is lost the power window will still operate but without the express down feature.