Airbag control unit with part number 635856800

What does the airbag control unit 635856800 do?

Control unit 635856800 controls the restraint system (SRS) for Hyundai. It checks the signals from the crash sensors, decides within milliseconds in an accident on airbags and seatbelt pretensioners, and monitors the entire system. It reports faults via the airbag warning light.

While driving, this work goes unnoticed, because the control unit checks sensors, wiring and trigger electronics in the background. If it finds a deviation, it records the finding in the fault memory.

After an accident it stores crash data and locks itself. This lock ends only with the repair.

Why does the control unit 635856800 fail?

Crash data stored after an accident is the most common cause, and this also applies when no airbag has been triggered. Other causes are aging components, cold solder joints, moisture at plug connections and voltage spikes.

A normal diagnostic tool cannot erase crash data. Airbag24 carries out the deletion as part of the repair.

Aging components lose reliability over time. Cold solder joints can arise from strain on the connection, and moisture attacks connectors as soon as corrosion sets in.

Voltage spikes occur, for example, with a weak battery or after a jump start, and additionally stress the electronics.

How can you tell that the 635856800 is defective?

A defect in the 635856800 shows up as the airbag warning light, which lights up permanently or intermittently, and as a fault message. If the diagnostic tool cannot connect to the control unit, or the fault memory cannot be cleared, a fault is also present. In an emergency, airbags and seatbelt pretensioners may then fail to deploy.

The light reports the finding immediately. Even without any visible irregularity while driving, the system may have recorded a fault.

Therefore have such a finding checked promptly, before you rely on the restraint systems.

Which vehicles is the 635856800 fitted in?

Control unit 635856800 is installed in these vehicles: Hyundai Tucson TL (2015-2018) and TL Facelift (2018-2020). The basis is the details we hold for this number.

In detail, the following vehicles are affected:

• Hyundai Tucson TL (2015-2018)
• Hyundai Tucson TL Facelift (2018-2020)

Compare the part number on the label of the removed unit with this page. Also have the fault memory read out, because only this result shows whether the control unit is defective or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 95910-D3000, 95910-D3010, 95910-D3020, 95910-D3030, 95910-D3130, 95910-D3200.

How does the repair of the 635856800 work?

First have the fault memory read out and attach the log. Then disconnect the battery and only then remove the control unit. Finally, create a repair order online and pack the unit well.

Airbag24 checks the unit on the test bench, repairs defective components, erases stored crash data and carries out a functional test. Processing usually takes 3–4 working days. Afterwards your own unit goes back to you.

Our repairs come with 2 years' statutory liability for defects. The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.

How does the control unit 635856800 get to Airbag24?

You send the unit as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns control unit 635856800 by UPS.

Put the printed repair order into the parcel and pack the unit shockproof.