Wiper System & Washer System - Except Electric: Other — Wiper System & Washer System - Except Electric — Wiper/washer Systems

Network Message Chart

Broadcast Message	Originating Module	Message Purpose
Vehicle speed	ABS	The ABS module sends this message to the BCM. The BCM sends this data to the windshield wiper motor. The windshield wiper motor uses this data for the speed sensitive wiper feature.
Transmission in reverse	PCM	The reverse gear input is used to engage the reverse gear wipe function.

BCM NETWORK INPUT MESSAGES

Windshield Wipers

The windshield wipers operate only when the ignition is in ACCESSORY or ON.

The SASM monitors the wiper/washer switch inputs and sends the wiper/washer switch data to the BCM through the LIN 1 (shared with the headlamp switch). Based on the input, the BCM sends the requested wiper speed data on the LIN 8 to the driver side windshield wiper motor. The driver side windshield wiper motor then coordinates the wiper operation with the passenger side windshield wiper motor (using an isolated communication circuit between the two of them) to prevent interference between the windshield wipers while they are operating.

The BCM also receives a second input through a fail-safe circuit from the SASM. This fail-safe circuit makes sure the windshield wipers function in the event a LIN 1 circuit communication failure occurs between the SASM and the BCM. If a failure occurs on the LIN 1, the wipers operate at LOW speed when the wiper/washer switch is in any position other than OFF.

If a communication failure occurs on the LIN 8 circuit between the BCM and the windshield wiper motor, the windshield wipers operate for 5 minutes at high speed, 5 minutes at low speed, 5 minutes at an intermittent timing, and then turn off.

Windshield Washer

When the washer switch is pulled towards the driver, the SASM sends the washer request to the BCM over the LIN. The BCM activates the windshield wash relay (internal to the BCM) and sends a message to the driver side windshield wiper motor. When the BCM activates the windshield wash relay, voltage is provided to the washer pump, directing washer fluid to the windshield. When the switch is released, the windshield wiper motor continues to activate the windshield wipers for 3 additional wipes and then turns the windshield wipers off.

Courtesy Wipe

If the windshield wiper switch is off when the windshield washer is requested, a few seconds after the windshield wash cycle has completed, an additional wipe of the windshield occurs to clear any remaining fluid that remains on the windshield.

Intermittent Wipers

When the wiper switch is in the intermittent setting, the wiper motor activates at timed intervals. The lower the setting, the longer the interval between wipes.

Speed Dependent Wipers

When the wiper/washer switch is in any intermittent setting except the lowest setting, the speed dependent feature increases the frequency of wiping as the vehicle speed increases to compensate for the extra moisture that accumulates on the windshield.

The BCM receives the vehicle speed from the ABS module. The BCM then sends the vehicle speed data to the driver side windshield wiper motor through the LIN.

Rain Sensitive Wipers (if equipped)

When equipped, the rain sensitive wiper feature replaces the intermittent wiper feature. The rain sensitive feature is active when the wiper/washer switch is in any of the 6 auto/intermittent sensitivity settings. The setting closest to OFF is the least sensitive to moisture, the highest setting being the most sensitive to moisture.

The rain sensor sends data through the LIN to the driver side windshield wiper motor. Based on the data received from the rain sensor and the auto/intermittent setting on the wiper/washer switch, the system automatically activates and adjusts the wiper speed and frequency when moisture is detected on the windshield.

If a fault is detected with the rain sensitive feature, the windshield wipers change to a default intermittent mode. The timing of the wipers correspond to a standard intermittent setting based on the auto/intermittent sensitivity setting on the wiper/washer switch.

Wiper Activated Exterior Lamps

The BCM turns the exterior lamps on within 10 seconds of the windshield wipers being activated by the wiper/washer switch when the headlamp switch is in the AUTO position. Approximately 30 seconds after the windshield wipers turn off, the BCM turns the exterior lamps off.

If equipped with rain sensitive wipers, the BCM turns the exterior lamps on when the rain sensitive wipers are activated by moisture detected on the windshield when the headlamp switch is in the AUTO position. Shortly after the rain sensitive wipers are deactivated (moisture no longer detected on the windshield), the BCM turns the exterior lamps off.

Rear Window Wiper

When the wiper/washer switch is in the INT 1 or INT 2 (continuous wipe) position, the SASM sends the request to the BCM through the LIN. When the request is received, the BCM supplies ground to the rear window wiper motor relay, activating the motor. The position of the wiper/washer switch determines how many times per minute the BCM provides ground to activate the rear window wiper motor.

The rear window wiper motor is self-parking.

Rear Window Washer

When the wiper/washer switch is pushed away from the driver, the SASM sends the request to the BCM through the LIN. The BCM energizes the rear washer relay (internal to the BCM) and activates the rear window wiper motor. When the BCM activates the rear window wash relay, voltage is provided to the washer pump, directing washer fluid to the rear window. When the switch is released, the rear window wiper motor continues to operate for 3 additional wipes and then turns off.

Reverse Gear Wipe

If the front wiper/washer switch is in any position other than off (or moisture is detected on the windshield with the rain sensitive wiper feature enabled, if equipped) and the vehicle is in REVERSE, the rear window wiper activates.

Wiper/Washer Switch

The wiper/washer switch is mounted directly to the SASM. The windshield wiper/washer inputs to the SASM are

Mist wipe
Windshield wash
Off
AUTO 1/INT 1
AUTO 2/INT 2
AUTO 3/INT 3
AUTO 4/INT 4
AUTO 5/INT 5
AUTO 6/INT 6
Low
High

The rear wiper/washer inputs to the SASM are

Off
INT 1
INT 2 (continuous wipe)
Rear window wash

Front Wiper Motor

The windshield wiper motors contains a logic module, internal sensors (to monitor the wiper arm position) and a multi-speed motor. The logic module from the driver side windshield wiper motor continuously monitors the wiper/washer switch inputs from the BCM and (if equipped) the rain sensor when the ignition is ON. Depending on the input, the wiper motor activates to achieve the desired request.

The driver side windshield wiper motor is the primary wiper motor and controls the operation of both windshield wipers.

There is no mechanical linkage between the motor and the wiper arm, the wiper arms are mounted directly to the wiper motors.

If a windshield wiper motor is replaced, the windshield wiper motors must be initialized.

Refer to: Windshield Wiper Motor Initialization .

Washer Pump

The washer pump is controlled by the BCM. The front and rear washer system share the same washer reservoir and a bi-directional washer pump. The washer pump delivers washer fluid to the windshield when the BCM activates the windshield washer relay (internal to the BCM), which provides voltage to the washer pump. Ground for the washer pump is provided through the rear washer relay (also internal to the BCM). When activated, the washer pump delivers washer fluid to the windshield.

When the BCM energizes the rear washer relay, the rear washer relay provides voltage to the washer pump. Ground for the washer pump is provided through the windshield washer relay (internal to the BCM). When activated, the pump delivers washer fluid to the rear window.

Rain Sensor

The rain sensor uses an infrared beam to optically sense water on the windshield. The intensity of the reflected beam is measured and compared to the intensity of the transmitted beam. If there is water on the surface of the windshield, the beam distorts, reducing the intensity of the beam. If the beam is not reflected completely, it is interpreted as rain on the windshield and the windshield wipers are activated.

A gel-type lens is used as the interface between the rain sensor and the windshield. If the lens is missing or damaged, the rain sensing wipers can be inoperative. The rain sensor gel-type lens can be replaced separately on a rain sensor of this type.

Rear Wiper Motor

The rear window wiper motor contains a single speed motor. When the BCM momentarily energizes the rear window wiper motor relay, the rear window wiper activates. A separate power circuit is used to continue the rear window wipe and park the rear window wiper.

All Windshield Wiper Modes Are Inoperative From One Or Both Windshield Wiper Motors

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.

REFER to: DIAGNOSTIC METHODS .