AutoCodes – Generic – B3808

B3808 Code - Rear Door Lock Relay Circuit

Quick Answer

The Body Control Module (BCM) internally grounds the door lock relay control circuit for the rear door lock relay when it receives a class 2 message from the driver door module (DDM) or passenger door module (PDM). Common causes include Faulty Rear Door Lock Relay, Rear Door Lock Relay harness is open or shorted, Rear Door Lock 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: B3808 indicates Rear Door Lock Relay Circuit.
Common causes: Common causes include Faulty Rear Door Lock Relay, Rear Door Lock Relay harness is open or shorted, Rear Door Lock 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.

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Code Popularity 2,238

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 Mar 17, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3808 Description

The Body Control Module (BCM) internally grounds the door lock relay control circuit for the rear door lock relay when it receives a class 2 message from the driver door module (DDM) or passenger door module (PDM). When the BCM grounds the door lock relay control circuit the rear door lock relay is energized and locks the rear doors. The Diagnostic Trouble Code (DTC) sets if the door lock relay control circuit is shorted to ground or open for more then one second.

OBDII Code B3808 - Rear Door Lock Relay Circuit - AutoCodes.com — B3808 Code - Rear Door Lock Relay Circuit

What does this mean?

What are the Possible Causes of the DTC B3808?

Faulty Rear Door Lock Relay
Rear Door Lock Relay harness is open or shorted
Rear Door Lock Relay circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3808?

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 B3808 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 B3808 code?

Need more information on how to fix the B3808 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B3808 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B3808 Buick — Rear Door Lock Relay Circuit
B3808 Cadillac — Rear Door Lock Relay Circuit
B3808 Chevrolet — Rear Door Lock Relay Circuit
B3808 GMC — Rear Door Lock 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 B3808 Code

1. What does OBDII code B3808 mean?

B3808 indicates an issue with the rear door lock relay circuit, which controls the locking and unlocking function of the rear doors.

2. What are common symptoms of code B3808?

Symptoms include rear door locks not functioning, difficulty locking or unlocking the rear doors, and possible malfunction of the key fob or lock button.

3. What causes the B3808 code to appear?

Common causes include a faulty rear door lock relay, damaged wiring or connectors in the circuit, or a malfunctioning body control module (BCM).

4. How can I diagnose the B3808 code?

Start by checking the rear door lock relay, inspecting the wiring and connectors for damage, and testing the circuit with a multimeter to confirm proper voltage and continuity.

5. Can a blown fuse cause the B3808 code?

Yes, a blown fuse in the door lock control circuit can disrupt power to the relay and trigger this code.

6. Is it safe to drive with the B3808 code active?

Yes, it is generally safe to drive, but the rear door locks may not function properly, which could be a security concern.

7. How do I fix the B3808 code?

Repairs may include replacing the rear door lock relay, repairing or replacing damaged wiring or connectors, or reprogramming or replacing the BCM if needed.

8. How much does it cost to fix the B3808 code?

Repair costs vary but may range from $50 to $200 for a relay replacement. Wiring repairs or BCM replacement could increase costs significantly.

9. Can I fix the B3808 code myself?

If youâ€™re comfortable working with electrical components, you can inspect and replace the relay or repair wiring. Otherwise, professional diagnosis and repair are recommended.

10. Will clearing the B3808 code with a scanner solve the problem?

Clearing the code may temporarily reset the system, but the underlying issue must be addressed to prevent the code from returning.