AutoCodes – GMC – B389A GMC

B389A GMC Code - Environment Identification

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 Body Control Module (BCM), Body Control Module harness is open or shorted, Body 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: B389A GMC indicates Environment Identification.
Common causes: Common causes include Faulty Body Control Module (BCM), Body Control Module harness is open or shorted, Body 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.

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Code Popularity 1,552

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 16, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B389A GMC 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 modules between vehicles. The Body Control Module (BCM) is the keeper of the environment identifier. The instrument cluster, electronic brake control module, HVAC control module, inflatable restraint sensing and diagnostic module, Engine Control Module (ECM), and steering column lock module (if equipped) 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. The Diagnostic Trouble Code (DTC) sets when an incorrect immobilizer identifier was broadcast by the BCM.

OBDII Code B389A GMC - Environment Identification - AutoCodes.com — B389A GMC Code - Environment Identification

What does this mean?

What are the Possible Causes of the DTC B389A GMC?

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

How to Fix the DTC B389A GMC?

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 B389A GMC 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 B389A GMC code?

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Need Help with the Code?

Get the B389A GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

B389A 2014 GMC Sierra — Environment Identification
B389A 2015 GMC Sierra — Environment Identification
B389A 2016 GMC Sierra — Environment Identification
B389A 2017 GMC Sierra — Environment Identification
B389A 2018 GMC Sierra — Environment Identification

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 B389A GMC Code

1. What does the OBDII code B389A mean on a GMC vehicle?

The B389A code refers to "Environment Identification" and typically relates to a communication issue between vehicle modules or improper configuration settings.

2. What are the common symptoms of code B389A on a GMC?

Symptoms may include warning lights on the dashboard, such as the check engine or service light, and possible malfunction of certain vehicle systems.

3. What causes the B389A code to appear on a GMC vehicle?

Common causes include incorrect module programming, corrupted software, damaged wiring, poor electrical connections, or a faulty control module.

4. How can I diagnose the B389A code on my GMC?

Use an advanced scan tool to check for related codes and communication errors, then inspect the wiring and connectors for damage or loose connections.

5. Can the B389A code be triggered by a dead battery?

Yes, a dead or weak battery can cause communication errors between modules, potentially triggering the B389A code.

6. Is the B389A code serious, and can I continue driving my GMC?

While the vehicle may still be drivable, the code could indicate underlying issues that might lead to system malfunctions, so itâ€™s best to address it promptly.

7. How can I fix the B389A code on my GMC?

Repairs may involve reprogramming the affected module, repairing or replacing damaged wiring, or updating the vehicleâ€™s software with the latest version.

8. Do I need a professional to fix the B389A code?

If you lack experience with automotive diagnostics and module programming, itâ€™s recommended to consult a professional technician for proper repair.

9. How much does it cost to repair the B389A code on a GMC?

Repair costs vary depending on the root cause but can range from $100 for minor fixes like wiring repairs to $500 or more for module reprogramming or replacement.

10. Can updating my GMCâ€™s software resolve the B389A code?

Yes, in some cases, updating the vehicleâ€™s software to the latest version can fix the communication issue and clear the code.