• | 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 |
---|---|---|---|---|
Windshield Washer Switch Signal | 2 | 1 | 1 | -- |
Windshield Washer Fluid Pump Control | 1 | 1 | 2 | -- |
Windshield Washer Relay Control | 2 | 1 | B3873 00 | -- |
Windshield Washer Switch Low Reference | -- | 1 | -- | -- |
Windshield Washer Fluid Pump Ground | -- | 1 | -- | -- |
1. Washer Inoperative 2. Washers Always ON |
The windshield washer function is controlled by the body control module (BCM). When the washer switch is pressed, ground is applied through the switch contacts and the signal circuit to the BCM indicating the wash request. The BCM then applies ground through the control circuit to the coil side of the FRT WASH relay energizing the relay. With the relay energized, battery voltage is applied through the switch contacts of the relay, the FRT WASH fuse and the control circuit to the windshield washer fluid pump.
Wiper/Washer System Description and Operation
Control Module References for scan tool information
⇒ | If the reading does not change between the specified values, refer to the Windshield Washer Switch Circuit Test. |
⇒ | If the test lamp does not turn ON and OFF while changing between the commanded states, refer to the Windshield Washer Pump Relay Control Circuit Test. |
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. |
⇒ | If not the specified value, test the signal circuit terminal L for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the windshield washer pump is on, test the windshield washer pump relay control circuit terminal 15 for a short to ground. If the circuit tests normal replace the underhood fuse block. |
⇒ | If the windshield washer pump is not on, test the relay 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. |
⇒ | If greater than the specified range, replace the windshield wiper washer switch. |
Important: If the switch tests open in any switch position other than Off, test the signal circuits for a short to voltage before replacing the switch.
Switch Position | Resistance |
---|---|
Off | Infinite |
Mist | 300-364 Ω |
Delay 1 | 3.48k-4.25k Ω |
Delay 2 | 2.52k-3.08k Ω |
Delay 3 | 1.78k-2.18k Ω |
Delay 4 | 1.17k-1.44k Ω |
Delay 5 | 697-851 Ω |
Low | 300-364 Ω |
High | 300-364 Ω |
⇒ | If any switch position is not within the specified range, replace the turn signal multifunction switch. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, setup, and programming |