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

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

The airbag control unit AB39-14B321-GA is the central control unit of the restraint system (SRS) of Ford. It evaluates the crash sensors, decides in a crash within milliseconds on airbags and seatbelt pretensioners, and continuously checks the system for faults. It reports detected faults via the airbag warning light.

The unit holds the system's components together and passes the commands on to the airbags and seatbelt pretensioners. This coordination runs in the background, without you noticing anything.

After a crash, it stores crash data and locks itself.

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

The most common cause is crash data from an accident, even if no airbag has been triggered; a normal diagnostic tool cannot erase it. Other causes are aged components, cold solder joints, moisture at plug connections and voltage spikes.

The other causes in detail:

• Aged electronic parts
• Cold solder joints
• Moisture and corrosion at plug connections
• Voltage spikes, for example from a weak battery or a jump start

A diagnostic tool can only show which faults are stored. Whether the cause lies in the control unit itself is determined only by examining the unit.

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

A defect in the control unit AB39-14B321-GA can be recognised by the airbag warning light in the instrument cluster, which stays on permanently or intermittently. This may be accompanied by a fault message, a diagnostic tool without a connection and a fault memory that cannot be cleared.

The signs in detail:

• Airbag warning light on permanently or intermittently
• Fault message in the instrument cluster
• No connection to the diagnostic tool
• Fault memory cannot be cleared

In that case, the system may not deploy in an emergency. If the warning light is on, the system should be checked promptly.

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

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

Here is the list of vehicles for this part number:

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

Place the part number from the label of the removed unit next to this page. This only checks whether the unit fits. In addition, have the fault memory read out before removal, because only the 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 AB3914B321CF, KB3T-14B321-BD.

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

First have the fault memory read out; the log comes along later in the parcel. Only then disconnect the battery and remove the control unit AB39-14B321-GA. Then create a repair order online and send the unit in well packed. Processing at Airbag24 normally takes 3–4 working days.

Airbag24 checks the unit on the test bench, repairs defective components and carries out a function test. The stored crash data is removed in the process. The unit then returns to you as your own unit.

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-GA get to Airbag24?

For shipping you have two options: you send the control unit AB39-14B321-GA as a parcel, or you have it collected by UPS for an extra charge. After the repair, Airbag24 sends the unit back to you by UPS.

The printed repair order belongs in the parcel. Pack the unit shock-proof so that it arrives undamaged.