Airbag control unit with part number KK3T-14B321-AC

What does the airbag control unit KK3T-14B321-AC do?

The KK3T-14B321-AC is the airbag control unit that coordinates the restraint system (SRS) in the Ford vehicle. It constantly checks the sensors, calculates in an impact which seatbelt pretensioners and airbags respond, and detects faults. After an accident it stores crash data and locks itself.

An evaluation takes only milliseconds, because there is no time for queries in an accident.

Why does the control unit KK3T-14B321-AC fail?

Most often the cause of the KK3T-14B321-AC lies in crash data stored after an accident, even if no airbag has triggered. Besides this, there are ageing components, cold solder joints, moisture or corrosion at plugs, and voltage spikes, for example from a weak battery or jump-starting.

A normal diagnostic tool cannot remove the crash data, so it remains in the memory of the control unit.

The other causes relate to age and environment. Electronic components change over time, solder joints can go cold, and moisture attacks the contacts.

Voltage spikes stress the electronics when the battery is weak or the vehicle is started with an external power source.

How can you tell that the KK3T-14B321-AC is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently on the KK3T-14B321-AC, and an error message appears on the display. The diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared. Airbags and seatbelt pretensioners may then possibly not trigger in an emergency.

The vehicle thus reports the fault itself through this light, which gives a clear indication.

Whether a plug, a cable or the control unit itself is behind it only becomes clear when the fault memory is read.

Which vehicles is the KK3T-14B321-AC fitted in?

The KK3T-14B321-AC is fitted in these vehicles: Ford Transit 7 ’14 (from 2014). Check whether your car belongs to it using the label on the removed unit.

The individual models are listed here:

• Ford Transit 7 ’14 (from 2014)

Two separate steps help. First, compare the number on the label of the removed unit with this page; this only confirms that it is the correct unit. Second, have the fault memory read beforehand. Only this result shows whether the control unit itself is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers BK3T-14B321-AB, BK3T-14B321-AC, BK3T-14B321-AD, BK3T-14B321-BB, BK3T-14B321-BC, BK3T-14B321-BD.

How does the repair of the KK3T-14B321-AC work?

For the KK3T-14B321-AC, first have the fault memory read and enclose the log, then disconnect the battery and only then remove the control unit. Then create a repair order online and send in the well-packed unit. At Airbag24, testing, repairing and checking usually takes 3–4 working days.

Airbag24 tests the unit on the test bench, repairs defective components, erases stored crash data and carries out a function test.

The sequence is binding for your safety, because work on the restraint system is only done with the battery disconnected.

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 KK3T-14B321-AC get to Airbag24?

You send the KK3T-14B321-AC as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends it back to you by UPS.

The printed repair order goes into the parcel, and the unit must be packed shockproof.