Windows: Description and Operation

Power Window System Description

How The Circuit Works

The operation of the power windows is controlled by the main switch in the driver's power window master switch. When the main switch is in the "Off" position, only the driver's door window can be opened or closed. With the main switch in "On", all windows can be opened or closed by the driver's power window master switch, or each window by its respective switch. The driver's window also has an automatic down mode which is controlled at the driver's power window master switch.


Driver's Window

With the ignition switch in "Run" or "Start", and the driver's switch in "Up", current flows through the 35 amp fuse, the contacts of the power window relay, fuse 12, the "Up" contacts of the driver's switch, the power window control unit, and the driver's power window motor to ground. The motor contacts close and will stay closed until the driver's switch is moved from "Up" to "Off" or the window goes completely up. After the window goes completely up, the contacts open and the motor stops. This prevents the motor from overheating if the switch is held in the "Up" position after the window has gone completely up. With the driver's switch in "Down", current flows through the motor in the opposite direction.


Automatic Down (Driver's Window)

With the ignition switch in "Run" or "Start," voltage is applied to the coil of the power window relay. The contacts of the power window relay close and voltage is applied to the driver's power window master switch and the power window control unit. With the driver's switch pushed to the automatic down position, voltage is applied through the driver's switch to the power window control unit's down and down hold inputs. The driver's power window motor contacts close and current flows through the motor to ground. The motor runs and the window goes completely down. When the window reaches the completely down position, the driver's power window motor contacts open and the motor stops.

Passenger's Window

With the ignition switch in "Run" or "Start", voltage is applied to the coil of the power window relay. The contacts of the power window relay close and voltage is applied through fuse 13 to the RH front power window switch. With the main switch "On" and the RH front power window switch in "Up", current flows through the 35 amp fuse, the contacts of the power window relay, fuse 13, the "Up" contacts of the window switch, the RH front power window motor, back through the RH front power window switch, and the driver's power window master switch to ground. The motor runs and the window goes up. With the RH front power window switch in "down", current flows through the motor in the opposite direction. The LH and RH rear power window switches operate similarly.