GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this 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

WIPER SPEED 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

--

--

WIPER CONTROL Relay Control

B3715 00

1

4

--

WIPER SPEED 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

--

--

WIPER CONTROL 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

The BCM output is actively being requested.

Conditions for Setting the DTC

The BCM detects a short to B+ in the windshield washer pump 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 Verification

Ignition ON, wiper switch in the HIGH position. Verify the windshield wipers are cycling at the high speed.

Circuit/System Testing

  1. Ignition OFF, disconnect the X5 harness connector at the BCM.
  2. Install a 10A fused jumper wire between the WPR 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 HI relay control circuit terminal 21 for a short to ground. If the circuit tests normal, replace the underhood fuse block.
  5. If all circuits test normal, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Accessory Wiring Junction Block Replacement
    •  Control Module References for BCM replacement, setup, and programming