Wipe-After-Wash Mode

When the control knob of the multi-function switch is depressed toward the steering column to the momentary front WASH position for more than about one-half second while the wiper system is not operating, the SCM sends an electronic washer switch  status message to the TIPM. Then the TIPM directs battery current and ground to operate the washer pump/motor in the front wash direction and energizes the front wiper motor in a continuous low speed mode for as long as the switch is held closed (up to approximately 10 seconds). When the control knob is released, the TIPM de-energizes the washer pump/motor immediately, but allows the wiper motor to operate for two or three additional wipe cycles before it de-energizes the wiper motor and parks the wiper blades near the base of the windshield.

If the control knob is held inward for more than about 10 seconds, the TIPM will suspend washer pump/motor operation until the knob is released for about 2 seconds and then cycled back to the WASH position; however, the wipers will continue to operate for as long as the switch is held closed. The TIPM monitors the changing state of the wiper motor park switch through a hard wired wiper park switch sense circuit input. This input allows the TIPM to count the number of wipe cycles that occur after the control knob is released, and to determine the proper interval at which to de-energize the wiper motor to complete the WIPE-AFTER-WASH mode cycle.