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Circuit/System Description

For an overview of the component/system, refer to:Power Windows Description and Operation 

Circuit Description
B+ - M74D Window Motor - Driver Supplied from a fuse.
B+ - M74P Window Motor - Passenger Supplied from a fuse.
B+ - S79LR Window Switch - Left Rear Supplied from a fuse.
B+ - S79RR Window Switch - Right Rear Supplied from a fuse.
Signal - Down@M74D Window Motor - Driver The output circuit is switched to ground to activate the component.
Signal - Up@M74D Window Motor - Driver The output circuit is switched to ground to activate the component.
Signal - Express@M74D Window Motor - Driver The output circuit is switched to ground to activate the component.
Signal - Up@M74P Window Motor - Passenger The output circuit is switched to ground to activate the component.
Signal - Down@M74P Window Motor - Passenger The output circuit is switched to ground to activate the component.
Signal - Express@M74P Window Motor - Passenger The output circuit is switched to ground to activate the component.
Control - Up@M74LR Window Motor - Left Rear The output circuit is switched from ground to 12 V to activate the component.
Control - Down@M74LR Window Motor - Left Rear The output circuit is switched from ground to 12 V to activate the component.
Control - Up@M74RR Window Motor - Right Rear The output circuit is switched from ground to 12 V to activate the component.
Control - Down@M74RR Window Motor - Right Rear The output circuit is switched from ground to 12 V to activate the component.
Ground Chassis Ground
Component Description
S79D Window Switch - Driver The S79D sends a serial data message to the K9 indicating the M74 function that has been requested.
M74D Window Motor - Driver
  • Power Window Control
  • The control module and the DC motor are one assembly.
S79P Window Switch - Passenger The switch has a normally open contact.
M74P Window Motor - Passenger
  • Power Window Control
  • The control module and the DC motor are one assembly.
S79LR Window Switch - Left Rear The switch has a normally open contact.
M74LR Window Motor - Left Rear An electric DC motor.
S79RR Window Switch - Right Rear The switch has a normally open contact.
M74RR Window Motor - Right Rear An electric DC motor.
K9 Body Control Module The module controls various vehicle functions like lighting, central door locking, power windows, etc.
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