Airbag control unit with part number AB39-14B321-DH

What does the airbag control unit AB39-14B321-DH do?

The airbag control unit AB39-14B321-DH coordinates the restraint system (SRS) of Ford. It assesses the sensor signals in a fraction of a second during an impact and decides which airbags and seatbelt pretensioners are triggered.

It also monitors the system during operation and shows detected faults via the airbag warning light.

After an accident it stores crash data, whereupon it locks itself.

Why does the control unit AB39-14B321-DH fail?

Most often this is because crash data was stored after an accident, even without an airbag being triggered. In addition, the AB39-14B321-DH can suffer from aged electronic components, cold solder joints, moisture and voltage spikes.

Such data stays in the unit until the repair, because a standard diagnostic tool does not reset it. The repair at Airbag24 deletes it.

The other causes concern the condition of the components. Solder joints can go cold, electronics age over time, and moisture reaches plug connections, where it causes corrosion. Voltage spikes, for example from jump-starting, additionally stress the unit.

How can you tell that the AB39-14B321-DH is defective?

The airbag warning light in the instrument cluster indicates a defect on the AB39-14B321-DH when it lights up permanently or intermittently. A fault message in the instrument cluster, a diagnostic tool without connection, or a fault memory that cannot be cleared may also occur.

In that case, airbags and seatbelt pretensioners may fail to trigger in an emergency. A prompt check is therefore sensible.

Which vehicles is the AB39-14B321-DH fitted in?

Several models come into question, so it is worth comparing with your own car. The AB39-14B321-DH is fitted in these vehicles: Ford Ranger 3 (2011-2015), 3 1st Facelift (2016-2019) and 3 2nd Facelift (2019-2023).

The list shows these models:

• Ford Ranger 3 (2011-2015)
• Ford Ranger 3 1st Facelift (2016-2019)
• Ford Ranger 3 2nd Facelift (2019-2023)

The part number is on the label of the removed unit; comparing it with this page only confirms that it is the right unit. Only the fault memory read out beforehand shows whether the control unit itself is affected or whether plugs and cables are the cause.

For the same vehicles, we also repair control units with the part numbers AB3914B321CF, KB3T-14B321-BD.

How does the repair of the AB39-14B321-DH work?

Start by having the fault memory read out and enclosing the log. Then disconnect the battery and remove the AB39-14B321-DH. Next, create a repair order online and send in the unit.

At Airbag24, checking, repair and testing generally take 3–4 working days. At the end there is a function test before the unit comes back; before that, Airbag24 deletes the crash data and rectifies defects on the components.

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 AB39-14B321-DH get to Airbag24?

You ship the AB39-14B321-DH as a parcel, or you book a UPS collection for an extra charge. The unit also comes back to you by UPS after the repair.

It is important that the printed repair order is in the parcel and that the unit is packed shockproof.