Airbag control unit with part number 8201236029

What does the airbag control unit 8201236029 do?

The airbag control unit 8201236029 forms the central control unit of the SRS in Renault. It evaluates the crash sensors, determines within milliseconds in the event of an impact whether airbags and seatbelt pretensioners are triggered, and checks the system continuously. After an accident it stores crash data and locks itself.

Without this device the sensors cannot control any triggering, which is why it has a special role in the system.

The warning is given via the airbag warning light in the instrument cluster as soon as the device records a fault in the restraint system.

Why does the control unit 8201236029 fail?

Most often the cause is crash data from an earlier accident involving the 8201236029, even if no airbag was fired, because a standard diagnostic tool does not touch this data. Aged components, cold solder joints, and moisture and corrosion on the connectors are also possible causes, as well as voltage spikes.

The data is the first point to check, because it affects the memory of the device.

Electronic components age, solder joints may have gone cold, and moisture causes contacts to corrode. Voltage spikes arise, for example, from a weak battery or when connecting to a jump start.

How can you tell that the 8201236029 is defective?

The airbag warning light in the instrument cluster lights up permanently or only intermittently, and a fault message also appears in the instrument cluster. If the diagnostic tool finds no connection to the 8201236029 or the fault memory cannot be cleared, that also indicates a defect. In such a case, airbags and seatbelt pretensioners may not trigger in an emergency.

The light alone says nothing about the affected component. Only reading out the fault memory reveals whether the control unit itself is affected or whether a line in the chain is causing the fault.

Warning light signs do not all appear at the same time as all the other symptoms. That is precisely why it is worth looking at the light after every switch-on.

Which vehicles is the 8201236029 fitted in?

The control unit 8201236029 is fitted in these vehicles: Renault Twingo II (2007-2014). Cross-check your model against the vehicle registration document.

The vehicles from the assignment are listed one below the other:

• Renault Twingo II (2007-2014)

Comparing the part number on the label of the removed device with this page only confirms that it is the right device. Having the fault memory read out, on the other hand, shows whether the control unit is defective or whether a connector or cable is behind it.

For the same vehicles, we also repair control units with the part numbers 402787B3, 8200 491 652, 8200054938, 8200111668, 8200491655, 8200896811.

How does the repair of the 8201236029 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only after that remove the control unit 8201236029. Then create a repair order online and send the well-packed device in.

Airbag24 checks the device on the test bench, repairs defective components, deletes the stored crash data and carries out a function test. Afterwards your device, repaired, is returned to you.

For the work at Airbag24, i.e. checking, repairing and testing, expect 3–4 working days as a rule.

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 8201236029 get to Airbag24?

Either you send the control unit 8201236029 as a parcel, or you book a UPS collection for an extra charge. After the repair, UPS delivers it back to you.

The repair order is printed and goes into the parcel, and the device must be packed shockproof.