Power Windows System Components
The following components are used to control the power windows:
• | Driver Door Module (DDM) |
• | Passenger Front Door Module (PDM) |
• | LH Rear Door Module (LRDM) |
• | RH Rear Door Module (RRDM) |
• | Driver Door Switch Assembly (DDSA) |
• | RH Front Power Window Switch |
• | LH Rear Power Window Switch |
• | RH Rear Power Window Switch |
• | LH Front Power Window Motor |
• | RH Front Power Window Motor |
• | LH Rear Power Window Motor |
• | RH Rear Power Window Motor |
• | Class 2 serial data circuit |
• | Power door serial data circuit |
• | PWR WDO 30 Amp Circuit Breaker |
| Driver Door Switch Assembly and Driver Door Module logic, Driver Door Module
internal driver operation |
| Front Passenger Door Module logic and internal driver operation |
| Left Rear Door Module and Right Rear Door Module logic and internal driver operation |
Power Windows Operation
The vehicle is equipped with power windows controlled by the door modules. Each
passenger door window can be operated, either from a switch built into the driver
door switch assembly (DDSA), or from a switch mounted locally to its associated door.
The driver door window can be operated only from the driver door window switch built
into the DDSA.
When a window is operated from the DDSA, the DDSA interprets the window switch
signal as a specific window switch request and sends the information to the driver
door module (DDM) via the power door serial data circuit. The DDM examines the request
and checks to see if it has received any class 2 serial data messages from any of
the other vehicle modules (i.e. ignition switch position) prohibiting the movement
of the window. If the window being operated is the driver door window, and if no prohibitive
class 2 messages have been received, the DDM then applies voltage and ground to the
driver door window motor to move the window glass as requested. If the window being
operated is a passenger door window, and no prohibitive class 2 messages have been
received, the DDM sends the request, via the power door serial data circuit, to the
appropriate passenger door module. The passenger door module then applies voltage
and ground to the passenger door window motor to move the window glass as requested.
When a passenger door window is operated from the power window switch mounted
locally to its associated door, the passenger door module first checks to see if
the DDM has received any prohibitive class 2 serial data messages. If there are no
prohibitive messages, the passenger door module powers the associated passenger door
window motor.
Both front door windows have the express down feature. This allows the front
door windows to be fully opened by momentarily pulling the appropriate window switch
lever to the second detente and then releasing.
Door Modules Power and Ground
In order to control power window operations, as well as other door functions,
door modules must be powered up. Battery voltage is supplied from the rear fuse block,
through separate circuits, to each door module. Each door module is separately grounded
through a ground stake. The door modules also use these voltage and ground supplies
to provide power and ground to their associated window and lock switches. The front
door modules, in addition, use these voltage and ground supplies for outside rearview
mirror operations.
The DDM battery voltage circuit is fed by the DRVMDL 10 amp fuse located in
the Rear Fuse Block.
The PDM battery voltage circuit is fed by the PASS MDL 10 amp fuse located in
the Rear Fuse Block.
The LRDM battery voltage circuit and the RRDM battery voltage circuit are both
fed by the RRDR MDL 10 amp fuse located in the Rear Fuse Block.
These circuits are in the C1 harness connector of each door module and must
not be confused with the door modules voltage and ground circuits that are used exclusively
to drive the power window motors. For more information concerning power window motor
power and grounds, see the appropriately titled paragraph following.
Window Motors Power and Ground
Each door module has its own separate battery positive voltage supply circuit,
used exclusively for power window motor operation. Although these circuits are separate,
they are united within the rear fuse block where they all are fed by the same PWR
WDO 30 amp circuit breaker. Each door module also has a separate ground circuit, connected
to a ground stake and used exclusively for power window motor operation. When a door
module drives a power window motor, the door module internally connects these voltage
and ground circuits to the appropriate window motor control circuits. The battery
voltage and ground circuits designated for window motor operation are in the C3 harness
connector of each front door module, and in the C2 harness connector of each rear
door module, and must not be confused with the battery voltage and ground circuits
of the C1 harness connector.
Driver Door Switch Assembly
The driver door switch assembly (DDSA) is wired to the DDM for power, ground,
and serial data communications. It has no other external circuits concerned with
power window operation. The DDSA internally supplies voltage and ground to the contacts
of the integral power window switches. When one of the window switches is operated
to Up, Down, or Express Down, the contacts for that function of the switch are closed
to ground and the DDSA recognizes the flow of voltage as a specific window switch
signal input. The DDSA then reports the switch activity to the DDM. The window switches
built into the DDSA are not serviced separately from the DDSA.
Front Passenger Door Power Window Switch
The front passenger door module supplies battery voltage to the two signal circuits,
and a ground to the ground circuit, of its associated window switch. One of the signal
circuits is for an Up signal, the other signal circuit is for a Down signal. When
the window switch is operated to the Up or Down position, the normally
open contacts for that function are closed to ground and battery voltage flows through
the circuits and the switch, providing the front passenger door module with the neccessary
signal input.
The front passenger door window can be operated in the express down mode from
the front passenger door window switch. The switch is constructed in a way that allows
for the contacts of the two signal circuits to indicate an express down command.
When the window switch lever is pulled to the second detente of the down position,
first the down signal contacts are closed, then the up signal contacts are closed.
The front passenger door module interprets this two contact signal as an express down
request.
Rear Door Power Window Switches
The rear door power window switches are similar to the front passenger door
power window switch, however, rear door windows do not have the express down capability.
Each rear door module supplies battery voltage to the two signal circuits, and a ground
to the ground circuit, of its associated window switch. One of the signal circuits
is for an Up signal, the other signal circuit is for a Down signal. When the window
switch is operated to the Up or Down position, the normally open contacts for that
function are closed to ground and battery voltage flows through the circuits and the
switch, providing the rear door module with the neccessary signal input.
Window Motors
Each door module applies battery voltage and ground, through the window motor
control circuits, to its associated window motor. The window motors are reversible.
The direction the window moves depends on which motor control circuit the voltage
is applied to, and which motor control circuit the ground is applied to.To move
the window in the Up direction, the module applies battery voltage to the window
motor up control circuit, and ground to the window motor down control circuit. When
a window Down movement is requested, the module reverses the polarity, applying
battery voltage to the window motor down control circuit, and ground to the window
motor up control circuit.
Window Lockout Feature
The window lockout switch is built into the Driver Door Switch Assembly (DDSA).
The lockout function can be programmed to prevent both rear windows from being operated
from their locally mounted switches, or, to prevent all of the passenger windows
from being operated from their locally mounted switches. When the lockout switch
button is momentarily pressed, the normally open contacts of the lockout switch
are closed, the LED indicator is illuminated, and the DDSA interprets the switch
signal. The DDSA then sends a message, via the power door serial data line, to
the driver door module (DDM) indicating that the switch is active. The DDM then sends
a message, via the power door serial data line, to both rear door modules to prohibit
the rear windows from being operated from the rear door window switches, or, sends
the message to all of the passenger doors to prohibit all passenger windows from
being operated from their respective switches. When the lockout function has been
activated, the windows can still be operated from the driver door by using the window
switches built into the DDSA.