For 1990-2009 cars

### 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: Wiper High Speed Relay Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Windshield Washer Switch Signal | 6 | 8 | 1 | --
Windshield Wiper Motor Relay Coil Supply Voltage | B3715 | 2 | 6 | --
Windshield Wiper Switch High Signal | 6 | 4 | 1 | --
Windshield Wiper Switch Low Signal | B3922 | 3 | 1 | --
Windshield Wiper Motor Park Switch Signal | 5 | 5 | -- | --
Windshield Wiper High Speed Relay Control | 7 | 4 | B3875 | --
Windshield Wiper Motor High Speed Control | 2 | 4 | -- | --
Windshield Wiper Motor Low Speed Control | 2 | 3 | -- | --
Windshield Wiper Motor Ground | -- | 2 | -- | --
Windshield Wiper Switch Ground | -- | 1 | -- | --
Wiper Relay Ground | -- | 2 | -- | --

1. Wipers and washers inoperative all modes
2. Wipers inoperative all modes and washers work
3. Delay or low speed wipers inoperative
4. High speed wipers inoperative
5. Wipers do not park
6. Wipers always on
7. Wipers operate at high speed in the low speed mode
8. Washer malfunction

### 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 Wiper Speed 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 in 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.

### Circuit/System Testing

1. Ignition OFF, disconnect the J2 harness connector at the engine fuse block.
2. Connect a test lamp between the control circuit terminal 21 and battery voltage.
3. Command the Wiper High Speed Relay ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the body control module.

⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the body control module.

4. If all circuits test normal, test or replace the engine fuse block.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming