Airbag control unit with part number 9642927880

What does the airbag control unit 9642927880 do?

The 9642927880 coordinates the restraint system in Citroën vehicles, meaning the airbags and the seatbelt pretensioners. To do this, it evaluates the signals from the crash sensors.

The decision is made within milliseconds. In addition, the unit monitors all components of the system and reports faults via the airbag warning light.

After an accident, it stores crash data and locks itself. The control unit is therefore at the centre of all occupant protection.

Why does the control unit 9642927880 fail?

In the 9642927880, the most common cause is crash data stored after an accident, even if no airbag has deployed. A normal diagnostic tool cannot erase this data. Other possible causes are aged components, moisture and voltage spikes.

The display in the vehicle reveals nothing about this. Only reading out the fault memory brings clarity.

In addition, aged electronic components and cold solder joints can play a part. Moisture and corrosion at plug connections have a similar effect.

Voltage spikes, for example from a weak battery or a jump start, put additional strain on the electronics.

How can you tell that the 9642927880 is defective?

A defect in the 9642927880 first shows up as the airbag warning light in the instrument cluster, which stays on continuously or intermittently. Other signs are an error message in the instrument cluster, a diagnostic tool with no connection to the control unit, and a fault memory that cannot be cleared.

As long as these indications persist, airbags and seatbelt pretensioners may not be able to deploy in an emergency. This also applies if the vehicle otherwise drives completely normally.

How far the defect reaches can only be determined by reading out the fault memory. The warning light alone is not enough for that.

Which vehicles is the 9642927880 fitted in?

The control unit 9642927880 is listed for Citroën vehicles. It is fitted in these vehicles: Citroën Xsara I Facelift (2000-2006) and I (1997-2000).

The list below names the affected vehicles.

• Citroën Xsara I Facelift (2000-2006)
• Citroën Xsara I (1997-2000)

First check the part number on the label of the unit against this page. This only confirms that you have the right unit in front of you. Also have the fault memory read out before you remove the control unit, because only this result shows whether the control unit is defective or a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 550535300, 550741100, 550776300, 9633504180, 9633621380, 9638101980.

How does the repair of the 9642927880 work?

First have the fault memory read out and attach the log. Then disconnect the battery, and only after that remove the control unit 9642927880. Afterwards, create a repair order online and send in the unit well packed.

At Airbag24, the unit goes through the test bench: defective components are replaced, crash data is erased, and a function test completes the repair. Processing usually takes 3–4 working days.

Afterwards your own unit is returned 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 9642927880 get to Airbag24?

You send the control unit 9642927880 as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 sends it back to you by UPS.

The printed repair order goes into the parcel, and you pack the unit so that it is shock-resistant.