Wipers and Washers - Front
Wipers and Washers - Front
Overview
The windshield wiper/washer system is activated by the wiper/washer switch. The wiper/washer switch is mounted to the SCCM (Steering Column Control Module). The following functions of the windshield wiper/washer system are available:
- Front windshield wipe/wash
- Wipers on with headlamps on
- Speed dependent wipers
- Rain sensitive wipers
- Courtesy wipe
System Operation
System Diagram
Network Message Chart
Module Network Input Messages
Windshield Wiper Operation
The wiper relay is activated whenever the ignition is in the ON position. The wiper relay provides voltage to the windshield wiper motor.
The wiper system is activated by the wiper/washer switch. The wiper/washer switch is mounted on the right side of the SCCM (Steering Column Control Module). The SCCM (Steering Column Control Module) commands the windshield wiper motor to activate the appropriate wash, low, high and intermittent modes through a private LIN (Local Interconnect Network).
When the wiper/washer switch is in the HIGH position, the windshield wiper motor also receives a ground signal which is hardwired directly from the SCCM (Steering Column Control Module) (bypassing the logic within the module). This fail-safe circuit makes sure that the windshield wipers will function in HIGH speed mode in the event of a LIN (Local Interconnect Network) communication failure.
Wiper Activated Headlamps
If equipped with automatic headlamps, the BCM (Body Control Module) illuminates the exterior lamps within 10 seconds of the windshield wipers being activated by the wiper/washer switch when the headlamp control switch is in the AUTOLAMP position. The BCM (Body Control Module) continues to illuminate the exterior lamps for approximately 30 seconds after the windshield wipers have been turned off.
If equipped with rain sensitive wipers (feature must be enabled through the message center) and the wiper/washer switch is in one of the 5 auto/intermittent settings, the BCM (Body Control Module) illuminates the exterior lamps within 30 seconds of the windshield wipers being activated by moisture detected on the windshield when the headlamp control switch is in the AUTOLAMP position. The BCM (Body Control Module) continues to illuminate the exterior lamps for approximately 60 seconds after the windshield wipers have been deactivated (moisture no longer detected on the windshield).
Speed Dependent Wipers
The speed dependent feature increases the frequency of wiping to compensate for the extra moisture that accumulates on the windshield as the vehicle speed increases. This feature activates when the wiper/washer switch is in any intermittent setting except the INT 1 position. As vehicle speed increases, the speed dependent feature gradually shortens the delay between wipes.
Rain Sensitive Wipers
The rain sensitive wiper feature replaces the intermittent wiper feature. To activate the rain sensitive wiper feature, position the wiper/washer switch to one of the 5 auto/intermittent settings. The auto/intermittent position closest to OFF is the least sensitive to moisture. The highest auto/intermittent position is the most sensitive to moisture. When the rain sensitive wiper system is active, the system activates the wipers and automatically adjusts the wiper speed when moisture is detected on the windshield. The rain sensitive wiper feature can be enabled/disabled through the message center. For additional information on enabling/disabling this feature, refer to the Owner's Literature.
Washer System
When the washer switch on the end of the wiper/washer stalk is pressed, the SCCM (Steering Column Control Module) sends the request to the windshield wiper motor through the LIN (Local Interconnect Network). The windshield wiper motor activates the wash relay (which is internal to the windshield wiper motor) providing voltage to the washer pump and directing washer fluid to the windshield.
Courtesy Wipe
When the windshield washer system is activated, the wipers cycle 3 times with washer fluid, followed by one final wipe a few seconds later to clear any remaining fluid that is dripping from the top of the windshield. This feature can be enabled/disabled through the message center. For additional information on enabling/disabling this feature, refer to the Owner's Literature.
Component Description
Front Wiper Motor
The windshield wiper motor contains a logic module, a 2-speed motor, 2 relays for wiper operation and one relay for washer operation. The logic module continuously monitors the inputs from the SCCM (Steering Column Control Module) whenever the ignition is in RUN or ACCESSORY and activates the appropriate relay(s) to achieve the desired driver request.
Wiper/Washer Switch
The wiper/washer switch provides the following inputs to the SCCM (Steering Column Control Module) for the front wiper/wash functions.
- AUTO 1/INT 1
- AUTO 2/INT 2
- AUTO 3/INT 3
- AUTO 4/INT 4
- AUTO 5/INT 5
- Low
- High
- Front washer
Washer Pump
The front and rear washer system share the same washer reservoir and a bi-directional washer pump. The pump delivers washer fluid to the windshield when the windshield wiper motor activates the internal washer relay, which provides voltage to the washer pump. Ground for the washer pump is provided through the rear washer relay located in the BJB (Battery Junction Box).