The LH window switch circuit provides input to the LH Door Control Module (LDCM) when the LH window switch is pressed. This input allows the LDCM to detect a window UP or DOWN request from the LH window switch. The LDCM provides power and ground to both of the window switches. When the LH window up switch is pressed, a ground is supplied through the LH window up switch to the LDCM window up input which is pulled low. When the LDCM detects low voltage on the LH window up input, the LDCM will command the LH window UP. If the LDCM detects low voltage on the LH window down input, the LDCM will command the LH window DOWN. If the RH window is operated from the LH window switch, the LDCM will send a message on the serial data line to the RH Door Control Module (RDCM) to operate the RH window UP or DOWN. The RH window operates the same as the LH window except the RDCM is receiving the RH window switch input and controlling RH window output functions. The DCMs provide both power and ground through CKT 164 and CKT 165 to the window motors. The up and down output operation is similar to each other except that the polarity of the voltage applied to the window motors is reversed.

The driver and passenger windows have an express down feature. This feature allows the DCMs to activate the LH or RH window DOWN without holding the window down switch for the entire duration. To activate this feature, momentarily press either window switch for one-third of a second and release. The DCMs will lower the selected window completely down. The express down feature can be stopped at any time by pressing the window switch again.