Principles of Operation

Wipers and Washers

Principles of Operation

Windshield Wiper Operation

The multifunction switch supplies ground inputs to the wiper/washer module (located behind the Smart Junction Box (SJB) to determine the wiper speed, including low, high and intermittent. The wiper/washer module also receives feedback from the wiper motor to determine the park position. The wiper/washer module sends power to the wiper motor through the high and low circuits.

Wiper Activated Headlamps (If Equipped with Autolamp System)

The SJB (Smart Junction Box) sends a voltage signal to the wiper/washer module in order to monitor the status of the wipers. When the wipers are turned on, the wiper/washer module will pull the voltage down. Once the SJB (Smart Junction Box) detects a drop in voltage it will turn on the headlamps after 3 seconds. When the SJB (Smart Junction Box) detects the voltage raising, it will determine that the wipers have been turned off and the SJB (Smart Junction Box) will turn off the headlamps after 30 seconds.

Rain Sensitive Wipers (if equipped)

The rain sensitive feature replaces the intermittent wiper feature. When the rain sensitive wiper system is active, the rain sensor sends data to the wiper/washer module. The wipers activate based on the amount of moisture detected on the windshield and the setting on the multifunction switch.

The rain sensor optically senses water on the windshield. An infrared beam lights a section of the windshield. The intensity of the reflected beam is measured and compared to the intensity of the transmitted beam. If there is water on the surface of the windshield, the beam distorts, reducing the intensity of the beam. If the beam is not reflected completely, it is interpreted as rain on the windshield and the windshield wipers are activated.

If a fault is detected with the rain sensor input by the wiper/washer module, the wiper/washer module to a default intermittent mode. The timing of the wipers correspond to a standard intermittent setting based on the selection on the multifunction switch.

A gel-type lens is used as the interface between the rain sensor and the windshield. If the lens is missing or damaged, the rain sensing wipers may be inoperative. If the rain sensitive wipers are inoperative and do not default to the intermittent mode, inspect the rain sensor and confirm that the gel-type lens over the rain sensor is undamaged.

Speed Sensitive Wipers

When the wiper control is set on any intermittent setting except INT 1, the speed dependant wipers will automatically adjust with the vehicle speed. Vehicle speed is supplied to the wiper/washer module from the PCM. The wiper/washer module is hardwired to the PCM. This feature decreases the time between wipes when the vehicle speed increases.