Principles of Operation

PRINCIPLES OF OPERATION

Front Wiper and Washers
The multifunction switch controls the front wiper/washer portion and is wired to the smart junction box (SJB). When the switch is moved to the desired position, one or more of circuits 56 (DB/OG), 58 (WH), 61 (YE/RD) or 63 (RD) is grounded. This will provide the necessary inputs for the SJB to control the run/park relay and the hi/low relay coils. In order to achieve high-speed operation, both relays are energized. The SJB will respond to the multifunction switch inputs only when the ignition lock cylinder is in RUN or ACC. The front washer pump relay is hard-wired to the SJB. The front washer switch portion of the multifunction switch will ground circuit 680 (LB/OG) which will signal the SJB to energize the washer pump relay. The relay will then provide voltage to the windshield washer pump through circuit 941 (BK/WH). The washer pump motor will then operate, for up to 10 seconds.

Intermittent Wipers
The intermittent wiper speed control allows one of five delay periods between each wiper swipe. The SJB controls delay as selected inputs from the multifunction switch on circuits 56 (DB/OG), 58 (WH) or 63 (RD) are grounded. The SJB then activates the wiper run/park relay at a chosen time interval specified by the multifunction switch. The interval wiper modes are vehicle-speed sensitive. When the vehicle is traveling between the speeds of 15 kp/h (9 mph) and 100 kp/h (62 mph), a variable dwell time is used for the interval modes that depends on the speed of the vehicle. When the vehicle is traveling below 15 up/h (9 mph) or above 100 kp/h (62 mph), a fixed dwell time is used for the interval modes.

Rear Wiper and Washer
The rear wiper and washer is controlled by the rear wash/wiper switch. The switch contains an internal module which activates the rear wiper and washer. When the rear wiper is selected, voltage is supplied to the rear wiper motor on circuit 410 (WH/OG), causes the motor to activate. When the washer is selected, the switch will send a ground signal to the rear washer pump on circuit 941 (BK/WH), causing it to operate which will also activate the rear wiper motor.

Smart Junction Box (SJB)
The SJB is a single component that distributes power to many systems in the vehicle that also has the functionality of an electronic control unit.