Airbag control unit with part number 8V51-14B321-BG

What does the airbag control unit 8V51-14B321-BG do?

As a central unit, the airbag control unit 8V51-14B321-BG controls the restraint system (SRS) for Ford. It reads the signals from the crash sensors, decides in an accident in a flash which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. It shows faults via the airbag warning light.

Monitoring runs in the background, and faults end up in the fault memory.

After an accident, the unit stores crash data and locks itself. The lock is only lifted by the repair.

Why does the control unit 8V51-14B321-BG fail?

Stored crash data counts among the most common causes on the 8V51-14B321-BG, even if no airbag has deployed. A normal diagnostic tool cannot erase it, but Airbag24 deletes it during the repair. Other causes are aged electronic components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes.

Crash data is created in the control unit after an accident. The fact that no airbag has deployed does not change this.

Over time, components lose reliability, and cold solder joints can cause contact problems.

Moisture and corrosion weaken the plug connectors. Voltage spikes, for example from a weak battery or a jump start, put a strain on the electronics. Which cause applies in each case is only clarified by reading out the fault memory together with an examination of the unit.

How can you tell that the 8V51-14B321-BG is defective?

The airbag warning light in the instrument cluster indicates a fault on the 8V51-14B321-BG when it lights up permanently or intermittently. At the same time, a fault message appears in the instrument cluster, and the diagnostic tool finds no connection to the control unit.

The fault memory cannot be cleared either. The warning light is one of the indicators you should keep an eye on in the instrument cluster.

In an emergency, the airbags and seatbelt pretensioners may then fail to deploy. Have the indicator checked.

Which vehicles is the 8V51-14B321-BG fitted in?

The control unit 8V51-14B321-BG is fitted in these vehicles: Ford Fiesta 7 ’09 (2008-2017). The list below gives the models in detail.

These vehicles are listed below:

• Ford Fiesta 7 ’09 (2008-2017)

First compare the part number on the label of the removed unit with this page, so that you have the right unit in front of you. Also have the fault memory read out before removal, because only this result 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 AA6T-14B321-CA, AA6T-14B321-EA, AA6T-14B321-FA, AE83-14B321-AD, AE83-14B321-AE, AE83-14B321-AF.

How does the repair of the 8V51-14B321-BG work?

First have the fault memory read out and enclose the log, then disconnect the battery and remove the control unit. Then create a repair order online and send the unit in, well packed. Airbag24 checks the 8V51-14B321-BG on the test bench, replaces defective components, deletes the stored crash data and carries out a function test; processing at Airbag24 usually takes 3–4 working days.

The order of these steps is part of the safety requirements for work on the airbag system. It applies to every removal.

You do not need to deal with the crash data yourself; the repair takes care of that.

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 8V51-14B321-BG get to Airbag24?

You send the control unit 8V51-14B321-BG in 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 shockproof.