AutoCodes – GMC – B3925 2017 GMC Sierra

B3925 2017 GMC Sierra Code - Incorrect Environmental Identifier Received from HVAC 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 Heating, Ventilation, and Air Conditioning (HVAC) Control Module, HVAC Control Module harness is open or shorted, HVAC 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: B3925 2017 GMC Sierra indicates Incorrect Environmental Identifier Received from HVAC Control Module.
Common causes: Common causes include Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module, HVAC Control Module harness is open or shorted, HVAC 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 202

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 B3925 2017 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, 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.
The Diagnostic Trouble Code (DTC) sets when the control module's environment identifier does not match the environment identifier stored by the BCM.

OBDII Code B3925 2017 GMC Sierra - Incorrect Environmental Identifier Received from HVAC Control Module - AutoCodes.com — B3925 2017 GMC Sierra Code - Incorrect Environmental Identifier Received from HVAC Control Module

What does this mean?

What are the Possible Causes of the DTC B3925 2017 GMC Sierra?

Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module
HVAC Control Module harness is open or shorted
HVAC Control Module circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3925 2017 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 B3925 2017 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 B3925 2017 GMC Sierra code?

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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 B3925 2017 GMC Sierra Code

1. What are common symptoms of OBDII code B3925 in a 2017 GMC Sierra?

The common symptoms include incorrect environmental control settings, inconsistent HVAC operation, and a malfunctioning climate control system.

2. What does the OBDII code B3925 on a 2017 GMC Sierra indicate?

The code B3925 indicates that the HVAC control module has received an incorrect environmental identifier, which can lead to issues with the climate control system.

3. What are possible causes of OBDII code B3925 in a 2017 GMC Sierra?

Possible causes include a faulty HVAC control module, wiring issues, a defective environmental sensor, or a communication error between modules in the vehicle.

4. How can I diagnose the OBDII code B3925 in my 2017 GMC Sierra?

Diagnosing the code involves using a diagnostic scanner to retrieve the specific code, checking the HVAC control module and related components for any visible damage, and testing the environmental sensor for proper functionality.

5. Can I still drive my 2017 GMC Sierra with the OBDII code B3925 present?

It is not recommended to drive the vehicle with this code present, as it can affect the proper functioning of the climate control system, leading to discomfort and potential safety issues while driving.

6. How can I repair OBDII code B3925 in my 2017 GMC Sierra?

Repairing the code may involve replacing the HVAC control module, fixing any wiring issues, replacing the environmental sensor, or reprogramming the control modules in the vehicle.

7. Is it possible to reset the OBDII code B3925 in a 2017 GMC Sierra without repairs?

While clearing the code with a diagnostic scanner is possible, it is essential to address the root cause of the issue to prevent the code from reoccurring.

8. Are there any DIY tips for troubleshooting OBDII code B3925 in a 2017 GMC Sierra?

DIY tips include checking the fuse related to the HVAC system, inspecting the wiring for any visible damage, and ensuring all connections to the HVAC control module are secure.

9. How much does it cost to repair OBDII code B3925 in a 2017 GMC Sierra?

The cost of repairing the code can vary depending on the specific cause and the required parts and labor. It is advisable to consult a professional mechanic for an accurate estimate.

10. Can a faulty environmental sensor trigger OBDII code B3925 in a 2017 GMC Sierra?

Yes, a defective environmental sensor can send incorrect data to the HVAC control module, triggering the B3925 code due to the mismatch in environmental identifiers.