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 activates the windshield wiper on/off relay (and the high speed wiper relay if for high speed wiper operation) to provide the requested operation.

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 this LIN, the wipers operate at LOW speed when the wiper/washer switch is in any position other than OFF.