Airbag control unit with part number 5WY67126

What is the function of the airbag control unit 5WY67126?

The airbag control unit with part number 5WY67126 is the central control module for the occupant restraint system (SRS) in the Daewoo Tosca V250. It is typically installed in the center console and is responsible for evaluating signals from crash sensors and, in the event of a collision, deploying the airbags and activating the seatbelt pretensioners. Additionally, it continuously monitors all system components and stores fault codes such as B1111.

As the “brain” of the entire restraint system, the unit constantly processes data from various acceleration and pressure sensors throughout the vehicle. Within milliseconds, it determines whether a crash has occurred and which safety components need to be activated to provide optimal protection for occupants.

At the same time, the control unit performs self-diagnosis of the system. Upon starting the vehicle, it checks all connected airbags, seatbelt pretensioners, and sensors. If irregularities or defects are detected, it illuminates the SRS warning light on the dashboard and records the corresponding fault in its internal memory.

Why does the airbag control unit 5WY67126 fail?

Defects in the 5WY67126 control unit primarily arise from internal electronic failures on the circuit board—such as issues with processors or capacitors caused by aging or moisture. Another common cause is the permanent storage of crash data after an accident, which can lock up the control unit. Interrupted cable connections to sensors may also result in persistently stored faults.

Electronic components like processors, capacitors, or memory chips themselves undergo natural aging. Vibrations and temperature fluctuations within the vehicle can, over time, lead to microscopic cracks at solder joints or failure of individual components on the circuit board, often resulting in an internal, non‑erasable fault.

Following a collision—even minor ones where the airbags do not deploy—the so‑called crash data is saved in the control unit’s memory. For safety reasons, this data permanently locks the device. Professional resetting is required, as simply clearing the fault memory is insufficient.

In rarer cases, external factors such as damaged cables—perhaps due to seat adjustments—can trigger error messages. The control unit interprets the broken connection as a defect and logs a permanent fault code, even though the internal hardware remains intact.

How can you recognize a defect in the 5WY67126 control unit?

A defective 5WY67126 airbag control unit typically manifests as a continuously illuminated SRS warning light on the instrument cluster. Often, the specific fault code B1111 (control unit malfunction) is stored in the fault memory. Another clear indication is that these fault codes cannot be cleared using a standard OBD2 diagnostic tool because they are permanently recorded.

The most obvious symptom for the driver is the persistently lit airbag or SRS indicator light. It does not turn off after the engine starts, signaling that the entire restraint system is disabled and would not activate in the event of a crash.

During workshop diagnostics, the B1111 fault code is frequently read, directly pointing to an internal defect in the control unit. This code indicates a problem either on the circuit board or within the unit’s memory.

A further typical feature is the stubborn persistence of the fault. Attempts to erase the fault memory using a standard diagnostic tool invariably fail; the error reappears immediately, as the underlying cause—whether a hardware defect or stored crash data—is deeply embedded within the device.

In which vehicles is the 5WY67126 control unit installed?

The airbag control unit with part number 5WY67126 is specifically designed for models manufactured by Daewoo. It is used in the Daewoo Tosca V250 series, covering both the original version and the facelift model. Airbag24 offers professional repair services for this control unit.

At Airbag24, we repair part number 5WY67126 for the following models:

Daewoo Tosca V250 (model years 2006–2010)

Daewoo Tosca V250 Facelift (model years 2010–2014)

How is the 5WY67126 airbag control unit professionally repaired?

Professional repair of the 5WY67126 control unit at Airbag24 includes a comprehensive diagnosis, deletion of stored crash data and persistent fault codes, and restoration of the electronics. Defective components on the circuit board are repaired or replaced. Since the original data is preserved, no re‑learning is required on the vehicle. We provide 2 years' statutory liability for defects on the repair.

With over 20 years of experience and more than 20,000 successful repairs, our process follows a proven procedure. After professional removal—where the battery must always be disconnected—the control unit is shipped to us.

Our technicians perform an incoming inspection and analyze the hardware. They then erase the stored crash data and all permanent error codes at the chip level. Defective electronic components such as processors, capacitors, or solder joints are identified and expertly repaired or replaced.

The key advantage of repair is that the original vehicle configuration remains intact. Once reinstalled, the control unit requires no new coding or adaptation and is immediately fully functional. This saves significant costs and time compared to purchasing a new part.