Principles of Operation (How Does It Work?)

Power Window Operation
The power window system operates under the control of the window safety relay. The window safety relay receives fused ignition voltage when the key is in RUN or ACCESSORY. The window safety relay when energized supplies power to the One Touch-Down (OTD) relay and the master power window switch.

Power Window Control
The power window system operate from the window switch located on each door panel. The RH power window can be operated from the LH master power window switch. The master power window switch has two modes of operation for the LH window, manual and auto.

Manual mode moves the window downward until the switch is released, the window will stop in that position.

The auto mode provides one-touch down (OTD) for the LH power window only. The OTD function allows the window to completely lower when the master switch is pressed and released.

Window Safety Relay
The window safety relay located in the Auxiliary Relay Box receives fused ignition voltage on pin 86, circuit 1002 when the key is in RUN or ACC. The 7.5 amp fuse is located in the Central Junction fuse box. The relay receives fused voltage on pin 87, circuit 170 at all times. The window safety relay is grounded on pin 85, circuit 57. when the ignition is turned to RUN or ACC contacts inside the relay close allowing voltage on pin 30, circuit 400.

One Touch Down Relay
The one touch down relay located in the Auxiliary Relay Box receives voltage from the window safety relay when the key is turned to RUN or ACC. Voltage is supplied on pin 5, and pin 1, circuit 400. The one touch down relay is under the control of the Generic Control Module (GEM). When the GEM senses a one touch down request from the master switch, the GEM will energize (supply ground) the OTD relay coil on pin 2, circuit 1007. The OTD relay will provide power to the LH front power window motor on pin 4, circuit 991 lowering the window. The one touch down feature will only operate when the ignition is in RUN or ACC.

The following inputs and outputs are features of the one touch down:
^ Ignition switch position.
^ One Touch Down Sense High Input.
^ One Touch Down Sense Low Input.
^ Down Window Command Input.
^ Up Window Command Input.

The outputs are:
^ One Touch Down Relay Output.

NOTE: The GEM/CTM must be reconfigured upon replacement.

Generic Electronic Module
The Generic Control Module (GEM) receives inputs and delivers outputs to a majority of electronically controlled features of the vehicle. The GEM constantly monitors the systems under its control and reports a concern in the form of a Diagnostic Trouble Code (DTC). The DTC can be retrieved by attaching a scan tool to the Data Link Connector (DLC) located beneath the instrument panel. There are two ways the GEM will receive inputs or deliver an output to operate a function or feature. The GEM can either receive and send inputs or outputs to a component, switch, or motor, that is directly hardwired to the GEM, or the GEM can receive and send inputs or output data to another module. The GEM control system has two modes of operation, the normal operating mode and tester-dependent diagnostics mode. The normal operating mode of the GEM detect errors and changes the GEM control strategy. There is no warning indicator for the GEM; therefore, a DTC concern will direct you to the GEM diagnostic procedures. The GEM can only detect open/short to GND faults when energizing a load, and short to battery faults when attempting to energize a load.