Power Windows System Components
The power windows system consists of the following components:
| • | Driver door module (DDM)--GMLAN device that receives and transmits messages and signals for window functionality. The DDM contains the driver door switch (DDS) which is integrated into the module. The DDS contains the driver, front
passenger, RR and LR window and window lockout switches. |
| • | Passenger front door module (PDM)--GMLAN device that receives and transmits messages and signals for window functionality. The PDM contains the front passenger door switch (PDS) which is integrated into the PDM. The PDS contains the front passenger
window switch. |
| • | Left rear power window switch--Provides switched voltage and ground window switch signals to the left rear window motor for left rear passenger window operation |
| • | Right rear power window switch--Provides switched voltage and ground window switch signals to the right rear window motor for right passenger window operation |
| • | Left front power window motor--Contains position sensors and a module that receives signals from the DDM and provides a status signal to the DDM |
| • | Right front power window motor--Contains position sensors and a module that receives signals from the PDM and provides a status signal to the PDM |
| • | Left rear power window motor--Contains position sensors and a module that receives signals from the left rear power window switch |
| • | Right rear power window motor--Contains position sensors and a module that receives signals from the right rear power window switch |
| • | DRIVER DR MOD fuse (15-amp) |
| • | PWR WNDW Circuit Breaker (25-amp) -- front |
| • | LT/REAR/WNDW fuse (15-amp) -- rear |
| • | REAR/WNDW fuse (15-amp) -- rear |
Power Window Controls
The driver power window is controlled by the driver window switch which also serves as the master switch for all windows. The passenger windows can be controlled by the power window switches located on the driver power window switch or from the power window
switch mounted locally on its associated door.
The power windows can be controlled in the following modes:
| • | Express Up -- front only |
Power Window Operation
The driver and front passenger doors are equipped with power window motors that contains its own module. Each power window motor receives a hot at all times battery supply voltage and constant ground source. When the right front passenger window switch
on the DDS is activated to the up or down position, the DDM will interpret the signal and send a GMLAN serial data message to the PDM. Upon receipt of the message, the PDM will send a signal to the front passenger window motor module on the GMLIN serial data
circuit. The window motor module will then supply battery voltage and ground to the window motor to drive the window motor to the up or down position.
The DDM communicates via the GMLAN serial data circuit with the body control module (BCM) to control the rear window functions from the driver master window switch. The BCM is hard wired to each rear power window switch with circuits for window up, window
down, and an enable circuit. The rear window switches contain internal logic that when supplied with voltage from the BCM over the enable circuit will driver the appropriate window in the direction commanded.
The rear power window switches are supplied with battery voltage from individual right and left WNDW fuses located in the rear fuse block. When a rear power window switch is activated to the DOWN position, voltage is applied to the motor down circuit and
the motor up circuit serves as the path to ground. The window motor will drive in the downward direction until the switch is released or the window has fully opened. When the window switch is activated to the UP position, voltage is applied to the motor up circuit
and the motor down circuit serves as the path to ground. Ground for the left rear power window switch is supplied at G200 and the right rear power window switch receives ground at G201.
Window Express Up and Down Operation
The express feature allows the windows to be fully opened or closed by momentarily pressing the window switch to the second detent of the up or down position. Due to safety concerns with express up functionality, the system is designed to detect objects
that become trapped between the window glass and window frame and reverse the direction of the window. This includes the use of window motor position sensors in each motor that determine the window position.
When a window switch is activated to an express up or down position, the door module associated with the power window switch will first receive the up or down signal and then the express signal is received. The door module will then send a signal over
the GMLIN serial data circuit to the appropriate power window motor. This will tell the window motor module that an express function has been requested. The window motor module will then supply battery voltage and ground to the motor to drive the window to the
full up or down position.
Window Lockout Feature
The window lockout switch is part of the master DDS. The lockout function is used to prevent the passenger door windows from being operated from their locally mounted switches. When the lockout switch is pressed momentarily, the switch contacts are briefly
closed, the LED indicator on the switch button is illuminated, and the DDM processes the switch signal. The DDM sends the switch status via GMLAN serial data to the PDM and the BCM. The DDM, PDM, and BCM will prohibit the passenger windows from being operated
from there locally mounted window switches. When the lockout function has been activated, the passenger door windows can still be operated from the driver door by using the DDS.
