B3873

DTC B3873

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B3873 01

-
Front Washer Relay Circuit Short to Battery

DTC B3873 02

-
Front Washer Relay Circuit Short to Ground

DTC B3873 04

-
Front Washer Relay Circuit Open

Diagnostic Fault Information






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 9-16 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

Wiper/Washer Schematics Electrical Diagrams

Connector End View Reference

Component Connector End Views Outside Rearview Mirror - Driver

Description and Operation

Wiper/Washer System Description and Operation Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Testing

1. Ignition OFF, Retained Accessory Power OFF, disconnect the harness connector X4 at the K9 body control module.

2. Test for 120-160 ohms between control terminal 14 and ground.

• If less than the specified value, test the control circuit for a short to ground.

• If greater than the specified value, test the control circuit for an open/high resistance or a short to voltage.

3. If all circuits test normal, test or replace the K9 body control module.

Component Testing

Output Control Test

1. Ignition ON, command the Windshield Washer Relay Command On and OFF with a scan tool.

2. Observe the KR11 windshield washer pump relay activates and the G24 windshield washer pump runs.

• If the KR11 windshield washer pump relay does not work, replace the X50A fuse block - underhood.

• If the KR11 windshield washer pump relay works but the G24 windshield washer pump does not work, test the KR6 rear window washer pump relay and the G24 windshield washer pump.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Windshield Washer Pump Replacement Windshield Washer Pump Replacement

* Fuse Block Replacement Fuse Block Replacement

* Control Module References Control Module References for BCM replacement, programming and setup