Diagnostic Instructions
| • | 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. |
DTC Descriptor
DTC B3873 01: Front Washer Relay Circuit Short to BatteryDTC B3873 02: Front Washer Relay Circuit Short to Ground
DTC B3873 04: Front Washer Relay Circuit open Circuit
Diagnostic Fault Information
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 | B3873 02 | B3873 04 | B3873 01 | -- |
Windshield Washer Fluid Pump Ground | -- | 1 | 1 | -- |
1. Front Washer Inoperative 2. Front Washer Always ON | ||||
Circuit/System Description
The body control module (BCM) controls the windshield washer fluid pump based on an input from the turn signal/multifunction switch. The BCM monitors the washer switch through the windshield washer switch signal circuit. When the wash switch is closed, ground is supplied to the front washer switch signal circuit. When this is the case, the BCM will command the windshield washer fluid pump and the low speed wipers on.
Conditions for Running the DTC
| • | Ignition ON. |
| • | The system voltage is between 9 V and 16 V. |
Conditions for Setting the DTC
| • | A short to ground or an open/high resistance is detected in the windshield washer relay control circuit. |
| • | A short to voltage is detected in the windshield washer relay control circuit. |
Action Taken When the DTC Sets
Washer operation is suspended.
Conditions for Clearing the DTC
A current DTC clears when the diagnostic runs and passes.
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Wiper/Washer System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for diagnostic tester information.
Circuit/System Verification
Operate the front washer by using the S78 Turn Signal/Multifunction Switch. Verify the G24 Windshield Washer Fluid Pump activates.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector X2 at the X50A Fuse Block - Underhood Primary.
- Connect a test lamp between the control circuit terminal X2 60 and ground.
- Ignition ON, command the rear washer ON and OFF using the S78 Turn Signal /Multifunction Switch. The test lamp should turn ON and OFF when changing between the commanded states.
- If all circuits test normal, test or replace the X50A Fuse Block - Underhood Primary.
| ⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module (BCM). |
| ⇒ | 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 K9 Body Control Module (BCM). |
Component Testing
Output Control Tests
Ignition ON, command the Windshield Washer Relay Command ON and OFF with a scan tool. Observe that the KR11 Windshield Washer Pump Relay clicks and the G24 Windshield Washer Fluid Pump runs.
| ⇒ | If the KR11 Windshield Washer Pump Relay does not work, replace the X50A Fuse Block - Underhood Primary. |
| ⇒ | If the KR11 Windshield Washer Pump Relay works, but the G24 Windshield Washer Fluid Pump does not run, test the control circuit. |
| ⇒ | If all circuits test normal, replace the G24 Windshield Washer Fluid Pump. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming. |
| • | LINK X , for UEC replacement. |
