Airbag control unit with part number P31295112

What does the airbag control unit P31295112 do?

The airbag control unit P31295112 is the central control unit of the restraint system (SRS) of Volvo. It evaluates the signals from the crash sensors, decides within milliseconds in an impact which airbags and seatbelt pretensioners to fire, and monitors the system continuously. It indicates faults via the airbag warning light.

The manufacturer's number Bosch 0285010729 is also printed on the housing. After an accident, the unit stores crash data and locks itself; only the repair lifts the lock.

Why does the control unit P31295112 fail?

The most common cause is crash data stored after an accident, even if no airbag was deployed; a normal diagnostic tool cannot erase it. Other causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes, for example from a weak battery or a jump start.

The crash data stays in the unit until it is removed, and Airbag24 erases it during the repair. An ordinary diagnostic tool cannot reach it.

Electronics age, and solder joints can give way over time. Moisture and corrosion at plugs disrupt the contact between components.

How can you tell that the P31295112 is defective?

The airbag warning light in the instrument cluster stays on or flickers, an error message appears in the instrument cluster, the diagnostic tool gets no connection to the control unit, or the fault memory cannot be cleared. Then airbags and seatbelt pretensioners may not deploy in a real crash.

The airbag warning light is the clearest sign. It indicates the fault as soon as the system has detected it, which is exactly its purpose.

An error message in the instrument cluster and a fault memory that cannot be cleared are further signs. If you notice any of these, have the system checked promptly.

Which vehicles is the P31295112 fitted in?

The P31295112 is fitted in these vehicles: Volvo XC90 C (2002-2006) and C Facelift (2006-2014).

The vehicles at a glance:

• Volvo XC90 C (2002-2006)
• Volvo XC90 C Facelift (2006-2014)

Two steps help before removal. Comparing the part number on the label of the removed unit with this page only confirms that it is the correct unit. Also have the fault memory read out. Only this log shows whether the control unit itself is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 0 285 001 656, 285001447, 285010210, 30724153, 30782386, 31295112.

How does the repair of the P31295112 work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only afterwards remove the control unit. Next, create a repair order online and send in the well-packed unit. Airbag24 generally needs 3–4 working days for the check, repair and test.

Airbag24 checks the unit on the test bench and replaces defective components. The stored crash data is erased, followed by 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 P31295112 get to Airbag24?

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

Put the printed repair order into the parcel, and pack the unit shock-proof.