B107F-49 - ECU must be replaced (clear crash data) (crash data stored) airbag control unit fault

What does error code B107F-49 indicate in the airbag control unit?

Error code B107F-49 signals a critical, internal electronic fault in the airbag control unit (ECU). This is typically triggered by permanently stored crash data following an impact, resulting in an irreversible module lockout for safety reasons. The system is disabled, and the error cannot be cleared using conventional diagnostic tools.

Technically speaking, the microprocessor within the control unit detects an uncorrectable condition that is written to the internal fault memory. The sub‑code “-49” specifically denotes an “Internal Electronic Failure.” This lockout is a manufacturer‑specified safety measure designed to prevent malfunction or unintended airbag deployment after a crash event.

The crash data is stored in a non-volatile memory area, usually an EEPROM chip. Once this entry is recorded, the control unit refuses normal operation and indicates a permanent system failure via the warning light. Restoration of functionality is only possible through targeted intervention at the chip level.

How can you recognize error B107F-49?

The primary symptom of error B107F-49 is the continuously illuminated airbag warning light on the instrument cluster. Additionally, the error code remains permanently stored in the airbag control unit’s memory and cannot be erased with standard workshop scanners. As a result, the entire airbag system is inoperative.

The warning light stays on continuously after starting the vehicle and does not extinguish as it normally would. This is a clear indication of a serious, safety‑related fault in the restraint system.

When attempting to read the fault memory with a diagnostic tool such as Multiecuscan, code B107F-49 is consistently displayed. Any attempt to clear the error fails, as the control unit rejects the erase request due to its internal lockout. In some cases, communication with the control unit may also be intermittently disrupted.

What causes error code B107F-49?

The primary cause of error code B107F-49 is the storage of crash data in the control unit’s internal memory after an impact. Less frequently, internal hardware defects—such as faulty circuitry, chips damaged by overvoltage, or moisture ingress—can also trigger this error.

Even minor accidents where no airbags deploy can generate sufficient impact to activate the sensors and initiate crash data recording. The control unit then preemptively enters a locked state.

Although B107F-49 is highly specific, functionally similar error codes exist across other manufacturers, indicating the same underlying defect. These include code B0100-49, commonly found in Fiat, Peugeot, and Citroën models, which likewise reports an internal electronic fault. Other general ECU error codes, such as B1000, DF001 (control unit defective), 65535 (control unit defective), or B0102 (malfunction), may point to related issues.

In which vehicles does error B107F-49 occur?

Error code B107F-49 is primarily diagnosed in certain vehicle models from Opel and Renault. Both newer model lines and older generations are affected, suggesting a specific configuration of airbag control units in these vehicles.

At Airbag24, we repair airbag control units exhibiting this error code for the following specific models:

Opel: Mokka B (from model year 2021 onward) and Vivaro C (from model year 2019 onward).

Renault: Mégane II (model years 2002–2009), Trafic IV, Twingo I (model years 1993–2007), and Kangoo II (model years 2008–2021).

How is error B107F-49 professionally repaired?

Professional repair involves targeted electronic intervention on the removed airbag control unit. Stored crash data is erased at the chip level, and the device’s software is restored to factory settings. A comprehensive functional test of the hardware is then performed to ensure full safety.

After submission to Airbag24, the control unit undergoes a standardized repair process. First, error B107F-49 is verified through an initial analysis. Next comes the decisive step: specialized programming hardware is used to directly access the memory chip (EEPROM) and remove the crash record.

Concurrently with data erasure, the circuit board undergoes visual and electrical inspection. Critical components—including processors, capacitors, and solder joints—are checked for potential damage caused by impacts or external factors like moisture. Defective parts are replaced according to industry standards.

After successful repair, the control unit is fully functional and free of errors. It can be reinstalled in the vehicle without any additional coding or programming (plug-and-play). We offer 2 years' statutory liability for defects on all our repairs.