Airbag control unit with part number P68185790AA

What does the airbag control unit P68185790AA do?

The P68185790AA is the airbag control unit of the restraint system (SRS) for Fiat. It evaluates the crash sensors, selects the appropriate airbags and seatbelt pretensioners within milliseconds in an accident and triggers them.

The unit continuously checks the wiring and components of the system. Faults appear via the airbag warning light in the instrument cluster.

After an accident it stores crash data and locks itself. What the crash data means for the repair is explained in the next section.

Why does the control unit P68185790AA fail?

Most often the cause is crash data stored after an accident, even if no airbag deployed; an ordinary diagnostic tool does not clear it. Further causes include ageing electronic components, cold solder joints, moisture and corrosion at plugs, and voltage spikes, for example from a weak battery or a jump-start.

Stored crash data remains in the control unit, regardless of whether an airbag has deployed. It cannot be cleared with a common diagnostic tool.

Electronics age, and solder joints can become brittle over the years. Moisture and corrosion at plug connections impair the contact.

Voltage spikes additionally load the circuit and should not be underestimated.

How can you tell that the P68185790AA is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently, an error message appears in the instrument cluster, and the diagnostic tool finds no connection to the control unit. If the fault memory also cannot be cleared, that points to a problem as well.

The warning light is a clear sign that the restraint system has detected a fault. In an emergency, the airbags and seatbelt pretensioners may then fail to deploy.

Follow up on such signs promptly and have the vehicle checked.

Which vehicles is the P68185790AA fitted in?

The P68185790AA is fitted in these vehicles: Fiat 500 312 (2007-2024).

Here you can see the list of vehicles for this part number:

• Fiat 500 312 (2007-2024)

Compare the part number on the label of the removed unit with this page to make sure you have the right unit. Also have the fault memory read out beforehand, because only the log 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 51782985, 51870005, 51897810, 51918659, 51963734, 519637734.

How does the repair of the P68185790AA work?

First have the fault memory read out and enclose the log. Then disconnect the battery before removing the control unit. Create the repair order online and send in the well-packed unit. Testing, repairing and checking at Airbag24 take 3–4 working days as a rule.

Airbag24 examines the unit on the test bench, replaces defective components where necessary, clears the stored crash data and carries out a function 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 P68185790AA get to Airbag24?

You send the unit in as a parcel or arrange a UPS collection for an extra charge. After the repair it comes back by UPS. The printed repair order goes into the parcel, and you pack the unit shock-resistant.

When packing, keep enough distance to the walls of the carton so the unit does not strike the edges.