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 |
| • | Passenger front door module (PDM) -- GMLAN device that receives and
transmits messages and signals for window functionality |
| • | Left rear door module (LRDM) -- GMLAN device that receives and transmits
messages and signals for window functionality |
| • | Right rear door module (RRDM) -- GMLAN device that receives and transmits
messages and signals for window functionality |
| • | Driver door switch assembly (DDSA) -- GMLAN device that contains
the driver, front passenger, RR and LR window and window lockout switches |
| • | Right front power window switch -- provides switched ground window
switch signals to the PDM for the front passenger window |
| • | Left rear power window switch -- provides switched ground window
switch signals to the LRDM for the left rear passenger window |
| • | Right rear power window switch -- provides switched ground window
switch signals to the RRDM for the right rear passenger window |
| • | 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 LRDM and provides a status signal to the LRDM |
| • | Right rear power window motor -- contains position sensors and a
module that receives signals from the RRDM and provides a status signal to the RRDM |
| • | DRIVER DR MOD fuse (10-amp) |
| • | FRT PASS DR MOD fuse (15-amp) |
| • | REAR DR MOD fuse (10 amp) |
| • | Power Window Motors Circuit Breaker (30-amp) |
Power Window Controls
The driver power window can be controlled by the driver window switch located
on the DDSA. The passenger windows can be controlled by the power window switches
located on the DDSA or from the power window switch mounted locally on its associated
door.
The power windows can be controlled in the following modes:
Power Windows Operation
Each door is equipped with a power window motor that contains its own module.
Each power window motor receives a hot at all times battery supply voltage and constant
ground source. When a window switch on the DDSA is activated to the up or down position,
the DDSA will interpret the signal and send a GMLAN message to the appropriate door
module. Upon receipt of the message, the door module will send a voltage signal to
the window motor module on the appropriate window motor signal circuit. The window
motor module will then supply battery voltage and ground to the window motor to drive
the window motor up or down.
When a power window is activated from a passenger door switch, the
operation is the same as described above except, the window motor signal circuits
are connected directly to the associated door module
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 the motor
that determine the window position. Before the express functionality may be used,
the window motor must be initialized. This requires operating the power window to
the full up and full down positions so the window motor module can learn the positions
of the up stop, down stop and the distance in between. The window module will then
report this status to the door module through the power window status circuit. For
further information on window initialization, refer to
Window Motor Programming - Express Function
.
When the window switch is activated to an express up or down position, the
door module will first receive the up or down signal and then the express signal is
received. The door module will then apply voltage to the power window up or down signal
circuit and then apply voltage to the apposing power window motor signal circuit.
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 DDSA. 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 DDSA
processes the switch signal. The DDSA sends the switch status via GMLAN serial data
to the passenger door modules. The passenger door modules then prohibit the windows
from being operated from the locally mounted passenger door window switches. When
the lockout function has been activated, the passenger door windows can still be operated
from the driver door by using the window switches built into the DDSA. the front passenger
window can be personalized to operate when the window lockout function is active.
Refer to
Vehicle Personalization
in Personalization.
