Airbag control unit with part number 28S5035758S

What is the function of the airbag control unit 28S5035758S?

The airbag control unit with part number 28S5035758S is the central control unit for the occupant safety system (SRS) in various model series of the Hyundai i20. It processes data from crash sensors and determines whether to deploy airbags and seatbelt pretensioners, thereby protecting vehicle occupants in the event of a collision.

Technically speaking, it is an SRS control unit specifically designed for Hyundai i20 models in the PB series (2008–2012), the PB facelift (2012–2014), and the GB facelift (2018–2020). Its primary task is continuous monitoring of all relevant system components.

In the event of a collision, the unit analyzes incoming signals from acceleration sensors and, upon exceeding predefined thresholds, deploys appropriate restraint devices such as the driver’s airbag, knee airbag, or seatbelt pretensioners.

This control unit is known under several equivalent part numbers, including 95910-1J400, 95910-1K100, 5WK43928, 28SC046902S, and 95910-C8200, which are often technically identical.

Why does the control unit 28S5035758S fail? Typical defects.

The most common cause of failure for the control unit 28S5035758S is the storage of crash data after an accident, which cannot be erased using conventional diagnostic tools. Other causes include internal electronic faults, undervoltage damage due to a weak battery, or external factors such as water damage.

After an airbag deployment, the control unit permanently stores a crash record in its internal memory. This entry locks the entire system and cannot be reset at a workshop, making repair or replacement unavoidable.

Internal electronic malfunctions are also a frequent cause. These can result from defective components, short circuits, or undervoltage when the vehicle battery or alternator is no longer functioning properly.

External influences, such as water damage—for example, from spilled liquids beneath the seats—can lead to corrosion and short circuits on the circuit board. Mechanical damage to cables or connectors can likewise impair functionality.

How do you recognize a defect in the control unit 28S5035758S?

A defect in the control unit 28S5035758S primarily manifests as a continuously illuminated airbag or SRS warning light on the instrument panel. Often, communication between the control unit and a diagnostic tool also ceases, and specific fault codes such as B1620 or B1102 are stored.

The clearest indication is the active airbag warning light. It may remain lit continuously, flash sporadically, or stay on for an unusually long time—such as 30 seconds—after the engine starts before finally extinguishing or remaining constantly illuminated.

Another critical sign is complete loss of communication. If a workshop attempts to read the fault memory via the OBD interface, no response is received from the airbag control unit, indicating a severe internal fault.

If fault codes such as B1346, B1102, B1620, or B1410 are detected and cannot be cleared, it strongly suggests that the root cause lies within the control unit itself. These codes point to specific internal or systemic issues.

In rare cases, other symptoms—such as a malfunctioning clock display or complete device failure when heated—may also indicate a defect. Important: Using simulators or resistors to bypass the fault is life‑threatening and will result in failure during the mandatory technical inspection.

In which vehicles is part number 28S5035758S installed?

The airbag control unit with part number 28S5035758S, along with its compatible variants, is exclusively used in various model years and series of the Hyundai i20. This includes both the first generation and later facelifted versions of this popular compact car.

At Airbag24, we repair the control unit 28S5035758S and its equivalent numbers for the following Hyundai models:

Hyundai i20 PB (model years 2008–2012)

Hyundai i20 PB facelift (model years 2012–2014)

Hyundai i20 GB facelift (model years 2018–2020)

How is the control unit 28S5035758S professionally repaired?

Professional repair of the control unit 28S5035758S involves precise diagnosis of the internal fault, erasure of permanently stored crash data, restoration of the electronics, and a final functional test. The unit is thus returned to the fully operational condition of a new component.

Before removal, a diagnosis at a specialized workshop is strongly recommended. This ensures that the fault truly originates in the control unit and not in an external component such as a sensor or wiring harness, thereby avoiding unnecessary expenses.

After submitting your unit to Airbag24, it is analyzed by specialized technicians. Using diagnostic tools, the internal fault memory is read out and the exact cause is identified—whether it’s a purely data-related error (crash data) or a defect in electronic components.

Following this, the actual repair takes place. Stored crash data is erased at the chip level, and any defective components on the circuit board are professionally replaced. The control unit is then recalibrated to ensure flawless functionality.

Once the repair is successfully completed and a thorough quality check has been performed, the control unit is returned to you. It is ready for immediate use upon installation. All repairs come with 2 years' statutory liability for defects.