Part 2

REAR WIPER/WASHER SYSTEM - WAGON ONLY




All rear wiper and washer system functions are initiated with the rear wiper and washer switch in the instrument panel switch pod located on the instrument panel center bezel, just above the radio and below the a/c outlets. Pushing the left side of the wiper/washer switch selects the rear wiper system operating mode (intermittent). it has fixed 10 seconds delay between wipe (not adjustable). indicator at bottom of the WIPE graphic will light up when the wipe switch is ON and goes away when the wipe is OFF. Depressing the momentary contact switch activates the rear washer system. When a rear wiper or washer mode is selected, the circuitry within the instrument panel switch pod sends an electronic rear wiper/washer switch status message over the Controller Area Network (CAN) data bus to the ElectroMechanical Instrument Cluster (EMIC) also referred to as the Cab Compartment Node (CCN). The CCN then sends electronic messages to the Front Control Module (FCM) over the CAN data bus requesting the appropriate rear wiper and washer system operating modes.

INTERMITTENT WIPE MODE
When the rear wiper switch is pressed to the left, the instrument cluster sends an electronic wiper switch message to the FCM, then the FCM electronic wipe logic circuit responds by selecting a predetermined length of time between wiper sweeps.

WASH MODE
When the rear washer control switch is depressed to the right in the momentary Wash position, the instrument cluster sends an electronic washer switch message to the FCM, then the FCM directs battery current and ground to the washer pump/motor. This will cause the washer pump/motor to be energized for as long as the Wash switch is held closed up to about ten seconds, and to de-energize when the rear wiper/washer switch is released.

WIPE-AFTER-WASH MODE
When the rear washer switch is released from the momentary Wash position, the instrument cluster sends an electronic washer switch message to the FCM. The FCM de-energizes the washer pump/motor, but allows the rear wiper motor to operate for several wipe cycles before it de-energizes the rear wiper relay.

OFF MODE
When the Off position of the rear wiper switch is selected, one of three events is possible. The event that will occur depends upon the position of the wiper blade on the liftgate glass and the mode the wiper motor is operating under at the moment that the Off position is selected. If the wiper blade is in the down position on the glass and the rear wiper system is operating in the intermittent cycle mode when the Off position is selected, the park switch is open and the FCM de-energizes the rear wiper relay control coil causing the rear wiper motor to cease to operate.

If the wiper blade is not in the down position on the glass and is operating in the intermittent cycle mode when the Off position is selected, the park switch is closed to ground and the FCM keeps the rear wiper relay control coil energized to operate the rear wiper motor until the rear wiper blade is in the down position on the glass and the park switch input is an open circuit.

The third event occurs with the rear wiper operating in the wipe-after-wash mode when the Off position is selected, in which case the FCM will continue to run the wiper motor until the completion of two wipes after wash before the rear wiper blade is parked. The FCM will also run the rear wiper motor to park the rear wiper blade if the ignition switch is turned to the Off position while the rear wiper system is still operating.