B3922

DTC B3922

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 Descriptor
DTC B3922 00
- Front Wiper Function Select Circuit

Diagnostic Fault Information






Circuit/System Description

The body control module (BCM) controls the wiper motor based on input from the windshield wiper washer switch. The BCM monitors the wiper washer switch through three separate signal circuits and a ground circuit. The windshield wiper switch high signal circuit is used to determine high speed wiper operation, the windshield wiper switch low signal is used to determine low speed, intermittent, and mist operation through the use of a resistor ladder, and windshield washer switch signal circuit is used to determine washer operation.

Conditions for Running the DTC

The ignition switch is in the ON position.

Conditions for Setting the DTC

The BCM detects a short to ground on the windshield wiper switch low signal circuit.

Action Taken When the DTC Sets

* The BCM will not activate the low speed output.
* The windshield wipers will only operate in the high speed mode.

Conditions for Clearing the DTC

* The DTC will clear the current status when the condition for setting the fault is corrected.
* A history DTC will clear after 50 consecutive ignition cycles without a fault present.

Reference Information
Schematic Reference

Wiper/Washer Schematics Electrical Diagrams
Connector End View Reference

Component Connector End Views Connector Views
Description and Operation

Wiper/Washer System Description and Operation (Wiper and Washers) Wiper/Washer System (Wipers and Washers)
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 Verification

Ignition ON, observe the scan tool Windshield Wiper Switch parameter while rotating the wiper switch. The reading should change between Off, Intermittent, and Low.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the turn signal multifunction switch.
2. Ignition ON, verify the scan tool Windshield Wiper Switch parameter is OFF.

• If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM.

3. If all circuits test normal, test or replace the turn signal multifunction switch.

Component Testing

Turn Signal Multifunction Switch
1. Ignition OFF, disconnect the harness connector at the turn signal multifunction switch.
2. With the wiper switch in the HIGH position, test for less than 2 ohm between the low reference terminal 2 and the signal terminal 3.

• If greater than the specified range, replace the windshield wiper washer switch.

Note: 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.

3. While cycling the wiper switch through each delay and speed position, test for the specified resistance between the low reference terminal 2 and the signal terminal 1.





If any switch position is not within the specified range, replace the turn signal multifunction switch.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Turn Signal Multifunction Switch Replacement Turn Signal Multifunction Switch Replacement
* Control Module References Control Module References for BCM replacement, programming, and setup