B2139 – OBD-II DTC

OBD-II DTC B2139 – Data Mismatch (receive data does not match what was expected)

DTC B2139 meaning

DTC B2139 refers to a “Data Mismatch” error in the On-Board Diagnostics II (OBD-II) system. This code indicates that the data received by the vehicle’s control module does not match the expected data. This discrepancy can occur in various systems, including the body control module (BCM) and other related components.

DTC B2139 symptoms

Common symptoms associated with DTC B2139 may include:

• Warning lights on the dashboard, such as the check engine light
• Malfunctioning electrical components, such as windows or locks
• Inconsistent performance of vehicle systems
• Loss of communication with certain modules

DTC B2139 causes

Several factors can lead to the occurrence of DTC B2139, including:

• Faulty wiring or connectors in the communication circuit
• Defective control modules, such as the BCM
• Software issues or programming errors in the control modules
• Corrosion or damage to connectors and terminals

DTC B2139 seriousness

The seriousness of DTC B2139 can vary depending on the specific symptoms and the systems affected. While it may not pose an immediate safety risk, it can lead to:

• Increased difficulty in operating certain vehicle functions
• Potential for further electrical issues if left unaddressed
• Complications during vehicle inspections or emissions testing

How to diagnose DTC B2139

To diagnose DTC B2139, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the DTC.
2. Check for any additional DTCs that may provide more context.
3. Inspect wiring and connectors related to the affected modules for damage or corrosion.
4. Test the affected control modules for proper operation.
5. Review the vehicle’s service history for any recent repairs or modifications.

How to fix DTC B2139 step-by-step instructions

To fix DTC B2139, follow these steps:

1. Inspect and repair any damaged wiring or connectors.
2. Replace any faulty control modules as necessary.
3. Update or reprogram the control modules if software issues are identified.
4. Clear the DTC using an OBD-II scanner.
5. Test drive the vehicle to ensure the issue is resolved and the DTC does not return.

How to erase DTC B2139

To erase DTC B2139, perform the following steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the diagnostic menu and select the option to clear or erase DTCs.
3. Confirm the action and wait for the scanner to complete the process.
4. Disconnect the scanner and start the vehicle to check if the DTC reappears.

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