Power Window System Components
The power window system consists of the following components:
| • | Driver power window master switch |
| • | Front passenger power window switch |
| • | RR power window switch (crew cab) |
| • | LR power window switch (crew cab) |
| • | Reversible power window motors in each of the doors - circuit breaker protected |
| • | PWR WNDW circuit breaker 25A |
Power Window System Controls
The power window system will operate anytime 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 there respective window.
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 switch are connected to ground and the switched side is connected to the accessory voltage circuit. By placing the driver power window switch in the down position, voltage is applied to the power window motor left front 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 left power window switch through the power window motor left front 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.
Window Lockout Operation
The window lockout switch is available on four door vehicles and is located on the driver power window master switch. When the window lockout switch is OFF, accessory voltage is available at each of the passenger power window switches through the window lockout control circuit and the closed contacts of the window lockout switch. The passenger power windows can be operated from their respective switches. When the window lockout switch is ON, the accessory voltage circuit is opened and the passenger window switches will be inoperative. The passenger power window switches on the driver power window master switch can control the up and down functions of the passenger power windows.
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 driver window switch and controls voltage and ground availability to the power window up and down circuits.
When the driver 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 driver 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.
