Airbag control unit with part number P8645271

What does the airbag control unit P8645271 do?

The airbag control unit P8645271 coordinates the restraint system (SRS) of Volvo. It processes the measured values of the crash sensors, decides in an accident within fractions of a second about airbags and seatbelt pretensioners, and monitors the system continuously. Faults appear on the airbag warning light.

After an accident, the unit stores crash data and locks itself. In addition, the unit carries the manufacturer number Bosch 0285001254.

Why does the control unit P8645271 fail?

The most common causes are crash data stored after an accident, which cannot be deleted with a normal diagnostic tool, even if no airbag was triggered. Other causes are ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

From the outside, it is not possible to tell which of these causes is present. At Airbag24, stored crash data is deleted during the repair.

Voltage spikes arise, for example, from a weak battery or from jump-starting, and corrosion on plugs can disrupt contacts.

How can you tell that the P8645271 is defective?

The airbag warning light in the instrument cluster stays on constantly or intermittently, and a fault message appears in the instrument cluster. The diagnostic tool gets no connection to the control unit, and the fault memory cannot be cleared.

If any of these signs appear, airbags and seatbelt pretensioners may not trigger in an emergency. Have the vehicle checked promptly.

Which vehicles is the P8645271 fitted in?

The control unit P8645271 is fitted in these vehicles: Volvo S60 P24 (2000-2009); Volvo XC70 P2 (2000-2004) and P2 Facelift (2004-2007); Volvo S80 TS (1998-2003) and TS Facelift (2003-2006); Volvo V70 S P26 (2000-2007).

The following overview lists the vehicles to which this part number is assigned.

• Volvo S60 P24 (2000-2009)
• Volvo XC70 P2 (2000-2004)
• Volvo XC70 P2 Facelift (2004-2007)
• Volvo S80 TS (1998-2003)
• Volvo S80 TS Facelift (2003-2006)
• Volvo V70 S P26 (2000-2007)

Compare the part number on the label of the unit with this page. That only establishes that it is the correct unit. Have the fault memory read out beforehand, because only this log shows whether the control unit is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 0 285 001 456, 285001254, 285001655, 30695741, 30721921, 30782385.

How does the repair of the P8645271 work?

At the start comes the reading out of the fault memory, the log of which you enclose. Only after disconnecting the battery do you remove the control unit P8645271. At Airbag24 the processing usually takes 3–4 working days.

Then create the repair order online and pack the unit well. Airbag24 checks it on the test bench, replaces defective components, removes stored crash data and carries out a function test.

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 P8645271 get to Airbag24?

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

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