Airbag control unit with part number CK4T-14B321-CF

What does the airbag control unit CK4T-14B321-CF do?

The airbag control unit CK4T-14B321-CF controls the restraint system (SRS) for Ford. It evaluates the sensor signals, determines in a collision within milliseconds which airbags and seatbelt pretensioners trigger, and monitors the system continuously.

It records faults in the fault memory and shows them via the airbag warning light. The monitoring covers sensors, wiring and triggering circuits.

After an accident it stores crash data and then locks itself.

Why does the control unit CK4T-14B321-CF fail?

The most common cause is stored crash data after an accident, even if no airbag was triggered; an ordinary diagnostic tool cannot delete it. Further causes include aged components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

The crash data remain in the unit until they are removed during the repair. Airbag24 takes over the deletion as part of the work on the control unit, after which the unit can be tested again.

The other causes relate to the electronics and their connections. Components lose reliability over time, solder joints can be faulty, and moisture attacks the contacts. Voltage spikes additionally stress the unit.

How can you tell that the CK4T-14B321-CF is defective?

A defect shows itself when the airbag warning light in the instrument cluster lights up permanently or intermittently and a fault message appears in the instrument cluster. In addition, there is a diagnostic tool without connection to the control unit and a fault memory that cannot be cleared.

• The airbag warning light in the instrument cluster lights up permanently or intermittently.
• A fault message on the airbag system appears in the instrument cluster.
• The diagnostic tool gets no connection to the control unit.
• The fault memory cannot be cleared.

In this case airbags and seatbelt pretensioners may possibly fail to deploy in an emergency. Have the warning light checked for that reason.

Which vehicles is the CK4T-14B321-CF fitted in?

The airbag control unit CK4T-14B321-CF is fitted in these vehicles: Ford Transit 7 ’14 (from 2014).

The list shows the assignment to this part number:

• Ford Transit 7 ’14 (from 2014)

Two points are important. Compare the part number on the label of the removed unit with this page, and you know that it is the right unit. Also have the fault memory read out, because the log 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 BK2T-14B321-BF, BK3T-14B321-AC, DT1T-14B321-DF, KT1T-14B321-KD, LK4Z-14B321-C, LK4Z-14B321-E.

How does the repair of the CK4T-14B321-CF work?

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

At Airbag24 the unit is checked on the test bench, defective components are repaired and the crash data is deleted. A function test concludes the work, after which your own unit goes back.

The 3–4 working days apply only to checking, repairing and testing at Airbag24. 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 CK4T-14B321-CF get to Airbag24?

You send the control unit CK4T-14B321-CF as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends it back by UPS.

Place the printed repair order in the parcel and pack the control unit shock-proof.