• | 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 |
---|---|---|---|---|
Accessory Voltage | 1, 2 | 1, 2 | -- | -- |
Rear Wiper/Washer Switch Accessory Voltage | 1, 2 | 1, 2 | -- | -- |
Rear Window Wiper Switch Signal | 1, 2 | 1, 2 | 3 | -- |
Rear Window Washer Fluid Pump Control | 2 | 2 | 3 | -- |
Rear Window Washer Pump Relay Control | 2 | 2 | 3 | -- |
Rear Window Wiper Motor Ground | -- | 1, 2 | -- | -- |
Rear Window Washer Fluid Pump Ground | -- | 2 | -- | -- |
1. All rear wiper washer system functions inoperative. 2. Rear washer pump inoperative. 3. Rear washer pump always on. |
The rear washer is activated based on an input from the rear washer switch. When the rear washer switch is pressed, B+ is applied through the rear window wiper switch signal circuit to the rear window wiper motor indicating the rear window washer operation request. The logic within the rear wiper motor interprets this request, then applies B+ through the rear window washer pump control circuit to the coil side of the REAR WASH relay, energizing the relay. Battery voltage from the REAR WASH fuse is then applied through the switch side of the relay to the washer pump.
Wiper/Washer System Description and Operation
Control Module References for scan tool information
⇒ | If the LIFT GATE AJAR message is illuminated, refer to Liftgate Ajar Indicator Malfunction. |
⇒ | If the rear wipers do not operate properly, refer to Windshield Wiper System Malfunction. |
⇒ | If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, test or replace the rear wiper/washer switch. |
⇒ | If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the rear wiper/washer switch. |
⇒ | If the test lamp illuminates, test the control circuit for a short to voltage. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the REAR WASH fuse for an open. |
⇒ | If the test lamp is always ON, test the relay control circuit for an short to voltage. If the circuit tests normal, replace the rear window wiper motor. |
⇒ | If the test lamp is always OFF, test the relay control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear window wiper motor. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the REAR WASH relay. |
⇒ | If not the specified value, replace the rear wiper/washer switch. |
⇒ | If greater than the specified range, replace the rear wiper/washer switch. |
⇒ | If the washer fluid pump does not activate, replace the rear window washer fluid pump. |
⇒ | If the resistance is not within the specified range, replace the relay. |
• | 30 and 85 |
• | 30 and 86 |
• | 30 and 87 |
• | 85 and 87 |
⇒ | If not the specified value, replace the relay. |
⇒ | If greater than the specified range, replace the relay. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.