Power Window System Components
The power window system consists of the following components:
• | Left front power window master switch |
• | Right front power window switch |
• | Left rear power window switch (4-door vehicles) |
• | Right rear power window switch (4-door vehicles) |
• | Window lockout switch (4-door vehicles) |
• | Reversible power window motors in each of the doors (circuit breaker
protected) |
Power Window System Controls
The power window system will operate anytime the Retained Accessory
Power (RAP) system is active or when the ignition switch is in the ACCY or
ON position.
The LF power window master switch can control the up and down functions
of all the windows in the vehicle. The passenger door power window switches
can only control the up and down functions of the individual window.
The power window master switch also contains a lockout switch (4-door
vehicles). The lockout switch controls the power window master switch
lockout signal circuit. When the lockout switch is in the OFF position,
the power window master switch lockout signal circuit is complete and
the passenger door power window switches function normally. When the
lockout switch is in the ON position, the power window master switch
lockout signal circuit is interrupted and the passenger door window switches
cannot control the up and down functions of the power windows.
Power Window Motor Operation
A permanent magnet motor operates each of the power side windows. Each
motor raises or lowers the glass when the motor receives voltage. The direction
the motor turns depends on the polarity of the supply voltage. The power
window switches control the polarity of the supply voltage. A built-in
circuit breaker protects each motor. The circuit breaker opens when
the switch is depressed for a extended period of time under the following
conditions:
• | The window has an obstruction. |
• | The window is fully open or fully closed. |
The circuit breaker will reset automatically as the circuit breaker
cools.
Power Window Operation
The normally closed contacts of the power window switch are connected
to ground and the center pole is connected to the accessory voltage circuit.
By placing the either power window switch in the down position, voltage
is applied to the power window motor down circuit and to the power window
motor. The other side of the power window motor is connected to ground through
the normally closed contacts of the power window switch through the power
window motor up circuit and drives the window down.
By placing the power window switch in the up position the polarity of
the motor is reversed and the motor drives the window up.
Express Down Operation
Vehicles equipped with the express down function incorporate an auto
down module in the power window master switch. The auto down module senses
the operation of the LF window switch and controls voltage and ground
availability to the power window up and down circuits.
When the LF power window switch is held in the down position for more
then 1 second, the auto down module supplies voltage to the power window down
circuit continuously until the power window reaches the bottom of its
travel. At this point, the auto down module senses an over current situation
on the power window down circuit and interrupts the voltage supply. If
the LF power window switch is actuated less then 1 second, the operation
is the same except the power window down circuit will be interrupted when
the switch is released.