• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Rear Window Wiper Switch Ignition Voltage | 1 | 1 | -- | -- |
Rear Window Wiper Switch Signal | 1 | 2 | 4 | -- |
Rear Window Washer Pump Relay Control | 1 | 3 | 5 | -- |
Rear Window Washer Pump Control | 3 | 3 | 5 | -- |
Rear Window Washer Pump Ground | -- | 3 | -- | -- |
1. All rear wiper washer system functions inoperative. 2. Rear wiper motor inoperative. 3. Rear washer pump inoperative. 4. Rear wiper motor always on. 5. Rear washer pump always on. |
The rear window washer pump is controlled by the rear window wiper washer switch through the rear washer pump relay. The ignition voltage is from the body control module (BCM), and when the WASH switch is pressed B+ is applied to the rear washer relay control circuit and to the rear wiper switch signal circuit. When the rear wiper motor module receives B+ on the rear wiper switch signal circuit, the wiper motor will operate continuously for as long as the voltage is present and several cycles after the switch is released. The rear washer relay control circuit is used to energize the relay coil and close the rear washer pump control circuit to B+.
Rear Wiper/Washer System Description and Operation
Control Module References for scan tool information
⇒ | If the rear wiper does not operate properly, refer to Rear Wiper System Malfunction . |
⇒ | If the test lamp does not turn on and off while changing between the commanded states, refer to the Rear Washer Pump Relay Control Circuit Test. |
⇒ | If the rear washer pump is on, test the control circuit terminal 3 for a short to voltage. If the circuit tests normal, refer to the Rear Washer Pump Circuit Test. |
⇒ | If the rear washer pump is not on, test the control circuit for an open/high resistance or short to ground. If the circuit tests normal replace the underhood fuse block. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the underhood fuse block. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the underhood fuse block. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.