Principles of Operation

PRINCIPLES OF OPERATION

Power Window Control
The driver power window one-touch down operation is controlled by the driver window control switch with integrated electronics. The one-touch down operation is requested by momentarily pressing the driver window down switch for 32 ms to 480 ms. The initial voltage input from the down switch starts the one-touch down operation. If the voltage input was less than 480 ms, the window/lock switch maintains the voltage supply to the window regulator motor down circuit. The battery junction box (BJB) circuit breaker 602 (20A) supplies the voltage to the switch through the accessory delay relay for this operation. The switch maintains the operation until one of the following conditions occur:
- 7 seconds expire.
- the switch detects the motor stalled by monitoring the current draw.
- a voltage input is received by the switch on either the up or down switch circuits.

From the switch, there is only one ground that is used for normal window operation and for one-touch down operation, making diagnostics simpler. If this ground is open, all window operation (one-touch and normal) is inoperative. The one-touch down electronics is incorporated into the master switch. The switch monitors voltage on the down circuit for the driver window. If the switch continues to detect voltage on the down circuit for more than 480 ms after initial activation, the switch does not affect operation. The down circuit through the switch is a direct connection to the motor in its normal state. This allows the driver window control switch to control the motor for normal operation. The passenger window motors are hardwired directly to the window control switches.

Accessory Delay
The accessory delay feature allows for operation of the windows after the engine has been turned off and the key removed. The accessory delay relay will remain energized for a predetermined length of time, or until a door is opened.

Heated Rear Window
The heated rear window is controlled by the electronic automatic temperature control (EATC). The ignition switch must be in RUN for the heated rear window to operate. Pressing the heated rear window control switch grounds the input to the EATC. If the module detects the ignition switch in RUN, ground is supplied to the heated rear window relay output. The heated rear window relay coil is energized which closes the contacts and supplies voltage to the antenna module. The antenna module then supplies voltage and ground to the heated rear window.