Windshield Wipers

The windshield wipers operate only when the ignition is ON.

The SASM monitors the wiper/washer switch inputs and sends the wiper/washer switch data to the BCM through a LIN (shared with the headlamp switch). Based on the input, the BCM sends the requested wiper speed data on a LIN 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 communication failure occurs between the SASM and the BCM. If a failure occurs on the LIN, the wipers operate at LOW speed when the wiper/washer switch is in any position other than OFF.