The outside moisture sensor monitors moisture accumulation on the windshield and uses a windshield wiper/washer switch status input to provide wipe commands to the windshield wiper/washer module. The DELAY positions on the wiper/washer switch are used to activate the AUTOMATIC rain sensing operating mode. They are also used to adjust the level of sensitivity to moisture accumulation, which determines the dwell time for commanding a wiper motor wipe cycle. Battery positive voltage is supplied to the outside moisture sensor through the accessory voltage circuit and RAIN SSR fuse located in the underhood fuse block. The sensor is grounded through the ground circuit. Whenever the ignition is in the run or accessory positions, the windshield wiper/washer module sends the wiper/washer switch status using a pulse width modulation (PWM) signal through the moisture sensor signal 1 circuit to the outside moisture sensor. When a wipe cycle is needed, the moisture sensor sends a PWM voltage signal through the moisture sensor signal 2 circuit back to the wiper/washer module requesting the wiper operation.

The outside moisture sensor uses the moisture sensor signal 2 circuit to command wiper motor wipe cycles and to confirm the moisture sensor signal 1 is being received. If at anytime communication between the moisture sensor and wiper/washer module is lost, the wiper/washer module will use the inputs from the windshield wiper/washer switch in the delay positions to operate the wiper motor at continuous variable delay intervals.

Schematic Reference

Wiper/Washer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Wiper/Washer System Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for Scan Tool Information

Ignition ON, wiper switch in the LO position. The windshield wipers should operate at low speed. If the windshield wipers do not operate, refer to Windshield Wiper System Malfunction.

1. Ignition OFF, disconnect the harness connector at the outside moisture sensor.
2. Test for less than 5.0 ohms of resistance between the ground circuit terminal 3 and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between accessory voltage circuit terminal 4 and ground.

⇒	If the test does not illuminate, test the accessory voltage circuit for a short to ground or an open/high resistance.

4. Ignition OFF, connect the harness connector at the outside moisture sensor.
5. Disconnect the connector at the windshield wiper /washer module.
6. Ignition ON, test for 8-10 volts between the signal circuit terminal A and ground.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the outside moisture sensor.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the outside moisture sensor.

7. Ignition ON, test for 4.0-8.5 volts between the signal circuit terminal H and ground.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the outside moisture sensor.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the outside moisture sensor.

8. If all circuits test normal, replace the windshield wiper /washer module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.