AutoCodes – Generic – B3875

B3875 Code - Windshield Wiper High Speed Relay Circuit

Quick Answer

The windshield wiper motor is controlled by the Body Control Module (BCM) through the windshield wiper replay and the windshield wiper speed control relay. Common causes include Faulty Windshield Wiper Relay, Windshield Wiper Relay harness is open or shorted, Windshield Wiper Relay circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: B3875 indicates Windshield Wiper High Speed Relay Circuit.
Common causes: Common causes include Faulty Windshield Wiper Relay, Windshield Wiper Relay harness is open or shorted, Windshield Wiper Relay circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 3,840

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B3875 Description

The windshield wiper motor is controlled by the Body Control Module (BCM) through the windshield wiper replay and the windshield wiper speed control relay. When low speed windshield wiper operation is requested, the BCM will apply voltage to the windshield wiper relay control circuit. This will cause the contacts in the windshield wiper relay to close and apply B+ to the windshield wiper motor through the windshield wiper low speed control circuit, enabling low speed wiper operation. When high speed windshield wiper operation is requested, the body control module continues to apply voltage to the windshield wiper relay control circuit and also applies ground to the windshield wiper speed control relay control circuit. This will cause the contacts in the windshield wiper speed control relay to close and apply B+ to the windshield wiper motor through the windshield wiper high-speed control circuit, enabling high speed wiper operation. When the windshield wiper request is no longer present, the contacts in the windshield wiper relay and windshield wiper speed control relay will open, removing B+ from the wiper motor control circuits. The windshield wiper motor will continue to operate using a discrete B+ circuit provided by the BCM until the wipers are in the park position.

OBDII Code B3875 - Windshield Wiper High Speed Relay Circuit - AutoCodes.com — B3875 Code - Windshield Wiper High Speed Relay Circuit

What does this mean?

What are the Possible Causes of the DTC B3875?

Faulty Windshield Wiper Relay
Windshield Wiper Relay harness is open or shorted
Windshield Wiper Relay circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3875?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3875 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the B3875 code?

Need more information on how to fix the B3875 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B3875 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B3875 Buick — Windshield Wiper High Speed Relay Circuit
B3875 Cadillac — Windshield Wiper High Speed Relay Circuit
B3875 Chevrolet — Windshield Wiper High Speed Relay Circuit
B3875 GMC — Windshield Wiper High Speed Relay Circuit

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B3875 Code

1. What does OBDII code B3875 mean?

Code B3875 indicates an issue with the windshield wiper high-speed relay circuit, which controls the high-speed operation of the wipers.

2. What are the common symptoms of code B3875?

Symptoms include windshield wipers not functioning at high speed, wipers stuck at one speed, or complete wiper failure.

3. What causes code B3875 to appear?

Common causes include a faulty high-speed wiper relay, damaged wiring or connectors, a malfunctioning wiper motor, or issues with the vehicleâ€™s control module.

4. Can I still drive my car with code B3875 active?

Yes, but driving in bad weather without fully functioning wipers can be unsafe, so the issue should be addressed promptly.

5. How can I diagnose code B3875?

Start by inspecting the wiper relay, wiring, and connectors for damage or corrosion. Use a multimeter to test the relay and circuit continuity.

6. Is replacing the wiper relay the only solution for code B3875?

No, while replacing the relay is a common fix, the issue could also stem from wiring, the wiper motor, or the control module.

7. How much does it cost to fix code B3875?

Repair costs vary but typically range from $50 to $200, depending on whether the issue is with the relay, wiring, or motor.

8. Can I fix code B3875 myself?

If you have basic automotive knowledge and tools, you may be able to replace the relay or repair wiring. For more complex issues, professional help is recommended.

9. How can I prevent code B3875 from occurring again?

Regularly inspect and maintain the wiper system, including cleaning connectors and ensuring the relay and motor are in good condition.

10. Will clearing the code B3875 with a scanner fix the problem?

Clearing the code may temporarily turn off the warning light, but it wonâ€™t fix the underlying issue causing the code. Proper diagnosis and repair are necessary.