Continuous Wipe Mode

When the LOW position of the control knob on the control stalk of the multi-function switch is selected the SCM sends an electronic wiper switch low  status message to the SAS over the LIN data bus. The SAS then relays an electronic wiper switch low  request message to the BCM over the CAN data bus. The BCM then directs battery current to the low speed brush of the wiper motor, causing the wipers to cycle at low speed.

When the HIGH position of the control knob is selected, the SCM sends an electronic wiper switch high  status message to the SAS. The SAS then relays an electronic wiper switch high  request message to the BCM. The BCM then directs battery current to the high speed brush of the wiper motor, causing the wipers to cycle at high speed.

When the OFF position of the multi-function switch control knob is selected, the SCM sends an electronic wiper switch off  status message to the SAS, the SAS relays an electronic wiper switch off  request message to the BCM, then one of two events will occur. The event that occurs depends upon the position of the wiper blades on the windshield at the moment that the control knob OFF position is selected.

If the wiper blades are in the down position on the windshield when the OFF position is selected, the park switch that is integral to the wiper motor is closed to ground, which provides a hard wired park switch sense input to the BCM. The BCM then de-energizes the wiper motor and the wiper motor ceases to operate. If the wiper blades are not in the down position on the windshield at the moment the OFF position is selected, the park switch is an open circuit and the BCM continues running the wiper motor at low speed until the wiper blades are in the down position on the windshield and the park switch input to the BCM is again closed to ground.