Airbag control unit with part number GU51-14B321-AA

What does the airbag control unit GU51-14B321-AA do?

The airbag control unit GU51-14B321-AA forms the switching centre of the restraint system (SRS) for Ford. It processes the signals from the crash sensors and decides in an impact which airbags and seatbelt pretensioners are triggered. After an accident it stores crash data and locks itself.

In operation the unit monitors the entire restraint technology. It checks the wiring, the sensors and the triggering of the airbags, so that everything is ready in an emergency.

The lock after an accident can only be lifted by the repair. Until then the unit reports any faults via the airbag warning light.

Why does the control unit GU51-14B321-AA fail?

The most common cause is stored crash data, which was saved in the unit after an accident, even if no airbag has deployed. A normal diagnostic tool cannot remove it. Other causes include ageing electronic components, cold solder joints, moisture and corrosion on plugs, and voltage spikes.

The fact that crash data can be erased means for you that Airbag24 removes it as part of the repair. A commercially available diagnostic tool cannot do this.

Ageing electronics and solder joints that give way also belong to the causes. Moisture and corrosion attack plug connections. Voltage spikes, for example from a weak battery or a jump start, can additionally strain the unit.

How can you tell that the GU51-14B321-AA is defective?

The airbag warning light lights permanently or intermittently, a fault message appears in the instrument cluster, the diagnostic tool cannot connect to the control unit, and the fault memory cannot be cleared.

Typical signs in everyday use are these points:

• Airbag warning light on, permanently or intermittently
• Fault message in the instrument cluster
• No connection between the diagnostic tool and the control unit
• Fault memory cannot be cleared

With such a finding, airbags and seatbelt pretensioners may fail to trigger in an emergency. The warning light shows the finding, so you should have it clarified promptly.

Which vehicles is the GU51-14B321-AA fitted in?

The control unit GU51-14B321-AA is fitted in these vehicles: Ford Transit 7 ’14 (from 2014).

The following vehicles are known to us for this part number:

• Ford Transit 7 ’14 (from 2014)

Compare the part number on the label of the removed unit with this page, which only confirms that it is the correct unit. Also have the fault memory read out beforehand, because only it shows whether the control unit is defective or whether a plug or cable causes the problem.

For the same vehicles, we also repair control units with the part numbers BK2T-14B321-BF, BK3T-14B321-AC, DT1T-14B321-DF, KT1T-14B321-KD, LK4Z-14B321-C, LK4Z-14B321-E.

How does the repair of the GU51-14B321-AA work?

First have the fault memory read out and enclose the log. Disconnect the battery and only then remove the control unit. Then create a repair order online and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days.

The order is fixed for safety reasons. The unit is removed only once the battery is disconnected and the log is available.

At Airbag24 the unit is checked on the test bench, defective components are replaced, the crash data is erased and a function test is carried out. 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 GU51-14B321-AA get to Airbag24?

You send the control unit GU51-14B321-AA as a parcel or book a UPS collection for an extra charge. After the repair, UPS brings the unit back to you.

Enclose the printed repair order and pack the unit shock-resistant.