B107E airbag control unit fault

What does error code B107E mean in the airbag control unit?

Error code B107E indicates a serious internal fault in the airbag control unit (SRS). This may be due to hardware damage, a software malfunction, or a module-specific issue. As a result, the airbag warning light illuminates and the entire restraint system is deactivated for safety.

Technically speaking, the control unit’s internal self-diagnosis detects an irreparable condition that compromises the reliable operation of the airbags and seatbelt pretensioners. The system shuts down to prevent false activations.

This error is often associated with other internal fault codes, such as B1000, which points to a general communication failure within the control unit, or B1015 and B207F, which describe specific SRS unit faults. The outcome is always the same: a non‑functional safety system.

How can you recognize error B107E?

The primary symptoms of error B107E are a permanently illuminated airbag warning light on the instrument cluster and the inability to clear the fault code using standard diagnostic tools. Communication with the control unit is frequently completely blocked.

The most noticeable sign is the activated airbag warning light. It does not turn off after starting the vehicle, signaling a critical system failure to the driver.

Another clear indication is the inability to perform diagnostics. When a workshop attempts to read or erase the fault memory, communication with the airbag control unit fails, or error B107E appears as permanent and unerasable.

Consequently, this condition results in a significant safety deficiency and is grounds for failing the main inspection (TÜV), as the restraint system is not operational.

What causes error code B107E?

The main causes of B107E are multifaceted, ranging from internal hardware and software defects in the control unit—such as permanently stored crash data—to external factors like moisture, corrosion, short circuits, or voltage issues in the vehicle’s electrical system.

An internal defect is the most common cause. This could involve a circuit board malfunction, a fault in the memory chips, or a software problem that disrupts communication and processing.

Stored crash data is another key factor. Even if no airbag deployed during an accident, the control unit retains irreversible data that locks the system and triggers error B107E.

External influences can also lead to this error. Penetrating moisture, for example from spilled beverages, causes corrosion on contacts or components. Cable breaks, short circuits, or an unstable power supply due to a faulty battery or alternator can likewise damage the control unit.

In some cases, the issue lies with a connected airbag module or its interface, causing the control unit to misinterpret it as an internal fault.

Which vehicles are affected by B107E?

Error code B107E occurs across brands in over 50 vehicle models. Manufacturers affected include BMW, Ford, Peugeot, Toyota, Kia, Nissan, and many others. Repairs are often relevant to specific model series and generations within these brands.

At Airbag24, we repair error code B107E for a wide range of vehicles, including: Alfa Romeo GTV 105; BMW X7 (G07, G07 LCI); Chevrolet Captiva (1st generation), Malibu (3rd & 6th generations); Citroën Nemo I; Dacia Logan (I, Van I) and Sandero I; Daewoo Korando K9; Daihatsu Boon (M300, M600, M700), Move Conte L575, Rocky F75, Sirion M600, and Taft LA900; Dodge Dakota (1st generation), Dart (2nd generation), and Ram (3rd generation); Fiat Croma 154; Ford B-Max I; Honda Civic EG; Hummer H2; Hyundai ix55 and Nexo FE; Infiniti G37 and Prototype 9 Concept; Kia Carens RP, K7 YG, Magentis MG, and Soul SK3; Land Rover Discovery L319; Lexus CT200h, IS XE30, and NX350; Mazda BT-50 UP; Mitsubishi Delica P20; Nissan Cefiro (A31, A32) and Skyline V37; Peugeot 5008 II, e-308 III, e-508 II, and iOn I; Pontiac 6000 LE, Bonneville (1992–1999), and LeMans; Porsche Carrera GT 980, Macan S, and Macan T (95B.2); Renault Kadjar I; Saturn Aura XE and Sky Red Line; Smart Fortwo EQ; SsangYong Korando e-Motion, Rexton (Y200, Y250, Y290, G4); Suzuki Aerio and Equator; Toyota Avalon Hybrid, Celica T200, iQ KGJ10, MR2 SW20, Noah (R60, Hybrid), Prius Prime, RAV4 (XA10, XA20, XA30, XA50), Supra Twin Turbo, Vios XP40, as well as Voxy (R60, R80, Hybrid) and Esquire Hybrid.

How is error B107E professionally repaired?

A professional repair of error B107E involves diagnosing the removed control unit, eliminating the internal root cause, erasing crash data, and restoring the original factory settings. Final tests ensure full functionality.

The process at Airbag24 begins after the control unit has been removed in a specialized workshop. The unit is sent in together with a repair form and, ideally, a diagnostic printout.

In the lab, a detailed analysis of both hardware and software is performed to pinpoint the exact source of the fault—whether it’s corrosion, a defective component, or a software issue. It’s important to note that no simulators or resistors are used, as this is both life‑threatening and illegal.

Subsequently, internal faults are corrected, crash data is erased, defective components are replaced, and the software is reset. Following successful repair and testing, the control unit is returned and can be reinstalled. Finally, only the fault memory in the vehicle needs to be cleared. We provide 2 years' statutory liability for defects on all repairs.

Repair vs. New Unit: The Advantages of Error B107E

Repairing the airbag control unit is the economically and technically superior solution compared to purchasing a new one. It delivers significant cost savings, preserves the vehicle’s original part, and avoids complex coding procedures.

The key advantage lies in cost. While a new control unit can exceed €500 depending on the model, a repair is considerably more affordable. For example, for a BMW X7, a repair price starting from approximately €65 is quoted, representing substantial savings.

Moreover, repair is faster and more efficient. Rather than waiting for a model‑specific new unit, the existing original control unit is refurbished. This maintains the vehicle’s configuration and eliminates the need for time‑consuming re‑coding or reprogramming.

A professional repair restores the device to its safe factory condition and is a method recognized by inspection organizations such as TÜV. With 2 years' statutory liability for defects, refurbishment offers a secure and sustainable alternative to costly replacement.