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 02
- Windshield Wiper Low Speed Signal Circuit Short to Ground
Diagnostic Fault Information
Circuit/System Description
The body control module (BCM) monitors the windshield wiper switch low signal circuit. When the wiper switch is place in the low position, battery voltage is applied through the switch contacts, a series of resistors, and the wiper switch low signal circuit to the BCM. The BCM then applies battery voltage through the wiper relay control circuit to energize the WPR Relay. When energized, battery voltage from the WPR Fuse is applied through the switch side of the WPR relay then through the switch side of the WPR HI relay to the windshield wiper motor.
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 A/C Compressor Clutch
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, disconnect the X3 harness connector at the turn signal/multifunction switch, ignition ON.
2. Verify a test lamp illuminates between the low reference circuit terminal H and B+.
• If test lamp does not illuminate
1. Ignition OFF, disconnect the harness connector at the K9 body control module.
2. Test for less than 2 ohms in the low reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K9 body control module.
• If test lamp does illuminate
3. Verify the scan tool Windshield Washer Switch parameter is not Active.
• If Active
1. Ignition OFF, disconnect the harness connector at the K9 body control module.
2. Test for infinite resistance between the signal circuit and ground.
• If less than infinite , repair the short to ground on the circuit.
• If infinite resistance, replace the K9 body control module.
• If not Active
4. Install a 3 A fused jumper wire between the signal circuit terminal L and the low reference circuit terminal H.
5. Verify the scan tool Windshield Washer Switch parameter is Active.
• If not Active
1. Ignition OFF, disconnect the harness connector at the K9 body control module.
2. Test for infinite resistance between the signal circuit and ground.
• If less than infinite , repair the short to voltage on the circuit.
• If less than 1 V
3. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K9 body control module.
• If Active
6. Test or replace the turn signal/multifunction switch.
Component Testing
Important: If the switch tests open in any switch position other than Off, test the wiper/washer switch signal circuits for a short to voltage before replacing the switch.
Multifunction Switch
1. Ignition OFF, disconnect the X3 harness connector at the turn signal/multifunction switch.
2. Rotate the wiper switch and compare the resistance readings to the values in the Windshield Wiper Switch Values table above for MIST, each DELAY and LOW speed.
3. Verify the correct resistance readings between signal circuit terminal L and low reference circuit terminal H.
• If the resistance values are not within the specified range
Replace the turn signal/multifunction switch.
• If the resistance values are within the specified range
4. Test for infinite resistance between signal circuit terminals L and K while rotating the wiper switch to MIST, each DELAY and LOW speed positions.
• If the less than infinite
Replace the turn signal/multifunction switch.
• If infinite resistance
5. Test for less than 5 ohms of between the signal circuit terminal K and low reference circuit terminal H.
• If greater than 5 ohms
Replace the turn signal/multifunction switch.
• If less than 5 ohms
6. Test for infinite resistance between signal circuit terminals J and low reference circuit terminal H.
• If less than infinite
Replace the turn signal/multifunction switch.
• If infinite resistance
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, setup, and programming