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 00: Front Washer Relay CircuitDiagnostic 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 | -- |
FRT WASH 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 | ||||
Circuit/System Description
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 from the FRT WPR fuse is applied through the switch contacts of the relay, the FRT WASH fuse, and the control circuit to the windshield washer fluid pump.
Conditions for Running the DTC
The BCM output is actively being requested.
Conditions for Setting the DTC
The BCM detects a short to B+ in the windshield washer pump relay control circuit.
Action Taken When the DTC Sets
The BCM will not activate the output.
Conditions for Clearing the DTC
| • | The current DTC will become history when the request for the output is removed or when the condition for setting the fault is corrected. |
| • | The history DTC will clear after 50 consecutive ignition cycles without a fault present. |
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 scan tool information
Circuit/System Verification
Operate the washers using the WASH switch. Verify the washer pump activates.
Circuit/System Testing
- Ignition OFF, disconnect the X4 harness connector at the BCM.
- Ignition ON, verify the windshield washer pump is not on.
- Install a 10A fused jumper wire between the relay control circuit terminal 15 and ground. Verify the windshield washer pump is on.
- If all circuits test 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 a short to voltage or an open/high resistance. If the circuit tests normal replace the underhood fuse block. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
