AutoCodes – GMC – B3981 2018 GMC Sierra

B3981 2018 GMC Sierra Code - Incorrect Environmental Identifier Received from Electronic Brake Control Module

Quick Answer

When certain modules are programmed and configured during installation, the module learns a specific environment identifier which is unique to the vehicle. Common causes include Faulty Electronic Brake Control Module (EBCM), Electronic Brake Control Module harness is open or shorted, Electronic Brake Control Module 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: B3981 2018 GMC Sierra indicates Incorrect Environmental Identifier Received from Electronic Brake Control Module.
Common causes: Common causes include Faulty Electronic Brake Control Module (EBCM), Electronic Brake Control Module harness is open or shorted, Electronic Brake Control Module 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 208

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 19, 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 B3981 2018 GMC Sierra Description

When certain modules are programmed and configured during installation, the module learns a specific environment identifier which is unique to the vehicle. The environment identifier is used to prevent the swapping of control modules between vehicles. The Body Control Module (BCM) is the keeper of the environment identifier. The Instrument Cluster, Electronic Brake Control Module (EBCM), Heating, Ventilation, and Air Conditioning (HVAC) Control Module, Inflatable Restraint Sensing And Diagnostic Module, and Telematics Communication Interface Control Module each learn the environment identifier during their configuration process. During vehicle operation, the BCM sends the immobilizer identifier as a challenge and each module responds to the challenge by sending the environment identifier back to the BCM. If the BCM sends an incorrect immobilizer identifier or a specific number of incorrect environment identifiers are received, vehicle starting is disabled.

OBDII Code B3981 2018 GMC Sierra - Incorrect Environmental Identifier Received from Electronic Brake Control Module - AutoCodes.com — B3981 2018 GMC Sierra Code - Incorrect Environmental Identifier Received from Electronic Brake Control Module

What does this mean?

What are the Possible Causes of the DTC B3981 2018 GMC Sierra?

Faulty Electronic Brake Control Module (EBCM)
Electronic Brake Control Module harness is open or shorted
Electronic Brake Control Module circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3981 2018 GMC Sierra?

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 B3981 2018 GMC Sierra 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 B3981 2018 GMC Sierra code?

Need more information on how to fix the B3981 2018 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B3981 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area

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 B3981 2018 GMC Sierra Code

1. What does the OBDII code B3981 mean for a 2018 GMC Sierra?

B3981 indicates that the vehicleâ€™s electronic brake control module (EBCM) has received an incorrect environmental identifier, which can result in communication or configuration issues.

2. What are the common symptoms of code B3981 in a 2018 GMC Sierra?

Symptoms may include warning lights on the dashboard, such as the ABS or traction control light, and potential loss of certain braking or stability functions.

3. What causes the B3981 code to appear in a 2018 GMC Sierra?

The code is typically caused by a misconfiguration, faulty programming, communication errors between modules, or a malfunctioning electronic brake control module.

4. Can a faulty electronic brake control module trigger the B3981 code?

Yes, a defective EBCM can cause incorrect data to be sent or received, leading to the B3981 code.

5. Is the B3981 code related to any safety concerns?

Yes, since it involves the brake control module, it could affect ABS, traction control, or stability systems, potentially impacting safety in certain conditions.

6. How can the B3981 code be diagnosed in a 2018 GMC Sierra?

A technician will use a professional scan tool to check for module communication issues, verify programming, and inspect wiring and connections related to the EBCM.

7. Can reprogramming the electronic brake control module fix the B3981 code?

In many cases, reprogramming or updating the EBCMâ€™s software can resolve the issue if itâ€™s caused by a configuration error.

8. Are wiring issues a possible cause of the B3981 code?

Yes, damaged or loose wiring and connectors between the EBCM and other modules can disrupt communication and trigger the code.

9. How much does it cost to fix the B3981 code on a 2018 GMC Sierra?

Repair costs can vary widely, from $100-$300 for reprogramming or minor fixes to $800-$1,200 if the EBCM needs replacement.

10. Can I continue driving with the B3981 code active?

Itâ€™s not recommended, as the code can affect critical safety systems like ABS and traction control, which are essential for safe driving conditions.