The rear wiper is controlled based on an input from the rear wiper/washer portion of the multifunction switch. When the switch is in the ON or DELAY, a voltage signal is sent to the rear window wiper motor indicating the desired speed. Each switch position has resistor that drops the voltage to a specified value which is interpreted by the rear window wiper motor as ON or DELAY.

Schematic Reference

Wiper/Washer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Rear Wiper/Washer System Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, observe the scan tool BCM Rear Closure Ajar Sw. parameter while opening and closing the liftgate and liftgate window. The reading should change between Active and Inactive.

⇒	If not the specified values refer to Liftgate/Liftgate Window Ajar Indicator Malfunction .

2. Press and release the rear window washer switch. The rear window wiper motor and pump will operate continuously for as long as the wash switch is pressed and several wipe cycles will occur after the switch is released.

⇒	If the rear wiper motor and the rear washer pump are inoperative , refer to the Rear Wiper Washer Switch Circuit Test.

⇒	If the rear washer pump operates normal and the rear wiper motor is inoperative, refer to the Rear Wiper Motor Circuit Test.

3. Operate the rear window wiper switch to DELAY, ON, and OFF. The rear window wiper motor will operate in a delayed wipe cycle mode then a continuous wipe cycle mode and stop in the park position.

⇒	If the wiper motor is inoperative in the DELAY or ON modes, refer to the Rear Wiper Motor Circuit Test.

⇒	If the rear wiper stops out of the park position, replace the rear window wiper motor.

Rear Wiper Washer Switch Circuit Test

1. Ignition OFF, disconnect the harness connector X4 at the turn signal multifunction switch.
2. Ignition On, verify that a test lamp illuminates between the ignition circuit terminal 1 and ground.

⇒	If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, refer to Power Mode Mismatch .

3. If all circuits test normal replace the turn signal multifunction switch.

Rear Wiper Motor Circuit Test

1. Ignition OFF, disconnect the harness connector at the rear window wiper motor.
2. Test for less than 1.0 ohm between the ground circuit terminal D and ground.

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

3. Verify that a test lamp illuminates between the B+ circuit terminal E and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for an open/high resistance or short to ground.

4. Ignition ON, test for B+ at the signal circuit terminal A while the rear window wiper switch is in the delay and on switch positions.

⇒	If B+ is not present, test the signal circuit for an open/high resistance or short to ground. If the circuit tests normal replace the turn signal multifunction switch.

5. If all circuits test normal replace the rear window wiper motor.

Rear Window Wiper Switch

1. Ignition OFF, disconnect the X4 harness connector at the turn signal multifunction switch.
2. Rear wiper switch OFF, test for infinite resistance between the ignition terminal 1 and the signal terminal 2.

⇒	If not the specified value, replace the turn signal multifunction switch.

3. Rear wiper switch in the ON position, test for 2000-2400 ohms between the ignition terminal 1 and the signal terminal 2.

⇒	If not within the specified range, replace the turn signal multifunction switch.

4. With the rear wiper switch in the DELAY position, test for 900-1.5K ohms between the ignition terminal 1 and the signal terminal 2.

⇒	If not within the specified range, replace the turn signal multifunction switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.