GM Service Manual Online
For 1990-2009 cars only

Power Windows

The vehicle is equipped with power windows controlled by the door modules. The DDM receives a window switch request, over the SBI serial data, from either the passenger door module wired to the window switch pressed or from the driver door switch assembly. The DDM checks the Class 2 serial data to see if the status information is correct (i.e. ignition switch position) to permit window operation.

If the status information to permit window operation is correct, the DDM sends the command to the door module controlling the window to move the window as requested.

Windows Power and Ground

The windows are powered by discreet power and ground circuits. These circuits are in the same dedicated connector as the window motor drive circuits.