B3811
DTC B3811
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 B3811 02
- Rear Washer Relay Circuit Short to Ground
Diagnostic Fault Information
Circuit/System Description
Rear Washer
When the Body Control Module detects that the Rear wiper/wash switch has activated the momentary Wash switch, it activates a High Side Drive output which supplies Battery to the coil of the Rear Washer Pump Relay. This energizes the Relay, which switches Battery Power to the Washer Pump Motor. The BCM will also activate continuous Low Speed Windshield Wipers as described above. This Washer and Wiper operation shall be continued so long as the switch remains active. Upon termination the Rear Wash Motor will be deactivated and the Wiper shall move to its Park Position and deactivate.
Conditions for Running the DTC
* Ignition ON.
* The system voltage is between 9-16 V.
Conditions for Setting the DTC
A short to ground is detected in the rear 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.
* 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 End Views By Name)
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 (Programming and Relearning) for diagnostic tester information
Circuit/System Verification
Operate the rear washers using the S80 Window Wiper/Washer Switch. Verify the G24 Windshield Washer Pump activates.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the X50A Fuse Block - Underhood.
2. Disconnect the harness connector X5 at the K9 Body Control Module.
3. Test for less than 5 ohm between the control circuit terminal 10 at the X50A Fuse Block - Underhood and the control circuit terminal 11 X5 at the K9 Body Control Module.
• If the value is not within the specified range, test the control circuit for a short to voltage or an open/high resistance.
• If the circuit tests normal, test or replace the K9 Body Control Module.
4. Test for infinite resistance between the control circuit terminal 10 at the X50A Fuse Block - Underhood and ground.
• If the value is not within the specified range, test the control circuit for a short to ground.
5. If all circuits test normal, test or replace the X50A Fuse Block - Underhood.
Component Testing
Relay Test
1. Ignition OFF, disconnect the harness connector X5 at the K9 Body Control Module.
2. Test for 60-200 ohm between control circuit terminal 11 X5 at the K9 Body Control Module and ground.
• If the value is not within the specified range, test the control circuit for a short to ground, short to voltage or an open.
• If all circuits test normal, test or replace the X50A Fuse Block - Underhood.
Output Control Test
Connect all harness connectors, ignition ON, Command the Rear Washer Relay Command On and OFF with a scan tool. Observe the KR6 Rear Window Washer Pump Relay clicks and the G24 Windshield Washer Pump runs.
If the KR6 Rear Window Washer Pump Relay does not work, replace the X50A Fuse Block - Underhood.
If the KR6 Rear Window Washer Pump Relay does work, but the G24 Windshield Washer Pump does not run, test the G24 Windshield Washer Pump ground and control circuit.
If all circuits test normal, replace the G24 Windshield Washer Pump.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming
* Relay Replacement (Attached to Wire Harness) (Relay Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (Relay Replacement (Within an Electrical Center))
* Windshield Washer With Seal Pump Replacement (Windshield Washer With Seal Pump Replacement)