Airbag control unit with part number DT1T-14B321-AF

What does the airbag control unit DT1T-14B321-AF do?

The airbag control unit DT1T-14B321-AF is the control unit of the restraint system (SRS) in Ford. It evaluates the crash sensor signals, decides within milliseconds in an accident whether the airbags and seatbelt pretensioners are triggered, and monitors the system permanently. It reports detected faults via the airbag warning light.

The monitoring covers the sensors, the firing circuits and the connections between them. It runs regardless of whether the vehicle is being driven.

After an accident the unit stores crash data and is locked afterwards.

Why does the control unit DT1T-14B321-AF fail?

Stored crash data is the most common cause, even when no airbag has triggered. It cannot be erased with a normal diagnostic tool. Other causes include aged components, cold solder joints, moisture and corrosion, and voltage spikes.

Root-cause analysis does not end with the crash data. Airbag24 erases them during the repair and then tests the unit.

The other causes are summarised in the following list:

• aged electronics
• cold solder joints
• moisture and corrosion at plug connections
• voltage spikes, for example from a weak battery or jump-starting

How can you tell that the DT1T-14B321-AF is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently. In addition an error message appears, and the diagnostic tool finds no connection to the control unit. The fault memory cannot be cleared, and airbags and seatbelt pretensioners may not trigger in an emergency.

The light indicates the defect and calls for action, even if it only comes on briefly. In that case do not wait, but have the display checked.

If the connection to the diagnostic tool is disturbed, the control unit need not be the cause. The fault memory read out will show what the problem is.

Which vehicles is the DT1T-14B321-AF fitted in?

The unit DT1T-14B321-AF is fitted in these vehicles: Ford Transit 7 ’14 (from 2014).

The list shows the vehicles for which this part number is recorded:

• Ford Transit 7 ’14 (from 2014)

Compare the part number on the removed unit with this page, so that you can be sure you have the correct unit in front of you. The comparison does nothing more than that. Having the fault memory read out beforehand, on the other hand, shows whether the control unit is defective or whether a plug or a 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 DT1T-14B321-AF work?

First have the fault memory read out and enclose the log. Then disconnect the battery and only then remove the control unit. Create a repair order online and send the unit in well packed. At Airbag24 the processing usually takes 3–4 working days.

Airbag24 tests the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. Afterwards your own unit is returned to you.

This time applies only to the work at Airbag24 and is not linked to your steps or to shipping.

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 DT1T-14B321-AF get to Airbag24?

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

The printed repair order goes into the parcel, and the unit is packed shock-proof.