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

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

The airbag control unit AB39-14B321-CE is the central control unit of the restraint system (SRS) for Ford. It evaluates the signals from the crash sensors, decides within a fraction of a second in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. If it detects a fault, it indicates this via the airbag warning light.

In the background the unit continuously checks all connected components. It records deviations in the fault memory so that a workshop can trace them.

After an accident the control unit stores crash data and locks itself.

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

The most common cause is crash data stored after an accident, even if no airbag was triggered; a normal diagnostic tool cannot erase it. Other causes are:

• aged electronic components
• cold solder joints
• moisture and corrosion at plug connections
• voltage spikes, for example from a weak battery or a jump start

Crash data arise after accidents in which no airbag triggers, and they remain in the memory until they are deliberately erased. A normal diagnostic tool cannot reach them.

The other causes concern the electronics themselves and partly show up only intermittently.

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

The airbag warning light in the instrument cluster lights up permanently or intermittently, and an error message appears. In addition, the diagnostic tool cannot establish a connection to the control unit, or the fault memory cannot be erased. In an emergency, airbags and seatbelt pretensioners may then fail to trigger.

The light shows a detected fault even when nothing unusual is noticed while driving. That is exactly why it deserves your attention.

If the light comes on only intermittently, have the fault memory read out anyway. The entry remains stored even when the indicator goes out again.

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

The control unit AB39-14B321-CE is fitted in these vehicles: Ford Ranger 3 (2011-2015), 3 1st Facelift (2016-2019) and 3 2nd Facelift (2019-2023).

The following overview names the vehicles for which the unit is listed:

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

Compare the part number on the label of the removed unit with this page. That tells you whether it is the right unit. Also have the fault memory read out, because only the result shows whether the control unit is defective or a plug or cable is 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-CE work?

First have the fault memory read out and enclose the log. Then disconnect the battery, remove the control unit, create a repair order online and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days; during this time Airbag24 checks the unit, repairs defective components, erases crash data and carries out a function test.

The order is mandatory for safety reasons. The control unit may only be removed after the battery has been disconnected.

After the function test Airbag24 sends your own unit back to you. The time covers only the work at Airbag24 and includes neither your steps nor the dispatch.

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-CE get to Airbag24?

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

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