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AutoCodes - Generic - B3981

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

- Code Popularity: 3,616 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC B3981?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • 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)
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How to Fix the DTC B3981?

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

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3981 code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code B3981 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 - Incorrect Environmental Identifier Received from Electronic Brake Control Module - AutoCodes.com
B3981 Code - Incorrect Environmental Identifier Received from Electronic Brake Control Module

Need More Information on the Code?

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Information for Specific Makes

  • B3981 Buick Incorrect Environmental Identifier Received from Electronic Brake Control Module  📷
  • B3981 Cadillac Incorrect Environmental Identifier Received from Electronic Brake Control Module  📷
  • B3981 Chevrolet Incorrect Environmental Identifier Received from Electronic Brake Control Module  📷
  • B3981 GMC Incorrect Environmental Identifier Received from Electronic Brake Control Module  📷

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Code B3981 comments

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