GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using the 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 B3875 00:  Wiper High Speed Relay Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

WPR HI Relay B+

1, 2

1, 2

--

--

Windshield Wiper Switch Signal

B3922 00

1

1

--

Windshield Wiper Switch High Signal

4

2

2

--

Windshield Wiper Motor Park Switch Signal

3

3

--

--

WPR Relay Control

B3715 02

1

4

--

WPR HI Relay Control

4

2

B3875 00

--

Windshield Wiper Motor High Speed Control

2

2

4

--

Windshield Wiper Motor Low Speed Control

1

1

4

--

Windshield Wiper Switch Low Reference

--

1, 2

1, 2

--

Windshield Wiper Motor Ground

--

1, 2, 3

--

--

WPR Relay Ground

--

1

--

--

1. Delay or low speed wipers inoperative

2. High speed wipers inoperative

3. Wipers do not park

4. Wipers always on

Circuit/System Description

The body control module (BCM) monitors the wiper high speed relay control circuit only when wiper high speed mode is active. When the wiper high speed mode is requested, the BCM responds by applying a ground through the wiper high speed relay control circuit to the coil side of the relay, energizing the WPR HI Relay.

Conditions for Running the DTC

This DTC can set only when the output is actively being requested by the BCM.

Conditions for Setting the DTC

This DTC sets if the BCM detects a short to battery voltage on the wiper high speed 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

Wiper/Washer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Wiper/Washer System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Ignition OFF, disconnect the X5 harness connector at the BCM.
  2. Install a 10A fused jumper wire between the Wiper 1 relay control circuit terminal 20 and B+.
  3. Ignition ON, verify that the high speed wipers are not on.
  4. If the high speed wipers are on, test the WIPER 2 relay control circuit terminal 21 for a short to ground. If the circuit tests normal, replace the underhood fuse block.
  5. Install a 10A fused jumper wire between the WIPER 2 relay control circuit terminal 21 and ground. Verify the high speed wipers are on.
  6. If the high speed wipers are 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.
  7. If all circuits test normal, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Underhood Electrical Center or Junction Block Replacement
    •  Control Module References for BCM replacement, setup, and programming