Airbag control unit with part number 51986773

What does the airbag control unit 51986773 do?

The airbag control unit 51986773 is the central control unit of the restraint system (SRS) for Fiat. It evaluates the signals from the crash sensors and decides in an accident, within milliseconds, which airbags and seatbelt pretensioners are triggered. After an accident it stores crash data and locks itself.

It also monitors the system continuously and reports faults via the airbag warning light in the instrument cluster.

Why does the control unit 51986773 fail?

With the control unit 51986773, the most common cause is crash data stored after an accident, even if no airbag has deployed. Other causes are ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

• Ageing electronic components
• Cold solder joints
• Moisture and corrosion at plug connections
• Voltage spikes, for example from a weak battery or a jump start

Crash data also arises when an accident turns out to be minor. The entry remains in the memory even if the vehicle then drives without any irregularities.

How can you tell that the 51986773 is defective?

A defect in the control unit 51986773 shows up as the airbag warning light in the instrument cluster, which stays on permanently or intermittently. Other signs include an error message in the instrument cluster and a fault memory that cannot be cleared.

If the diagnostic tool cannot reach the control unit, this also indicates a fault. In the event of a defect, airbags and seatbelt pretensioners may not deploy in an emergency. The warning light shows that the system has detected a fault; only reading out the fault memory shows which cause lies behind it.

Which vehicles is the 51986773 fitted in?

This list lets you check whether the control unit 51986773 belongs to your vehicle. The control unit 51986773 is fitted in these vehicles: Fiat Tipo 356 (2016-2020).

The vehicles for this part number are listed here:

• Fiat Tipo 356 (2016-2020)

Make the label comparison on the removed unit: if the part number on the label matches this page, it is the correct unit. Only the fault memory, read out beforehand, shows whether the control unit is defective or whether a connector or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 00052027042, 00052055639, 00052055640, 00052055641, 00052058730, 00052078052.

How does the repair of the 51986773 work?

First have the fault memory read out and enclose the log, then disconnect the battery and only then remove the control unit 51986773. Then create a repair order online and send in the well-packed unit. Processing at Airbag24, that is checking, repairing and testing, usually takes 3–4 working days.

Airbag24 checks the control unit on the test bench, replaces defective components and carries out a functional test. Your own unit is then 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 51986773 get to Airbag24?

You send the control unit 51986773 as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns it to you by UPS.

Put the printed repair order into the parcel and pack the unit shock-proof. Make sure that it does not shift in the carton and that the packaging is completely closed.