Airbag control unit with part number C1BT-14B321-AC

What does the airbag control unit C1BT-14B321-AC do?

The airbag control unit C1BT-14B321-AC coordinates the airbags and seatbelt pretensioners in the Ford. In an impact it evaluates the crash sensors and decides on triggering within milliseconds. Faults in the system are indicated by the airbag warning light.

The signals from several sensors are combined before the unit releases triggering. The unit works without any action by the driver.

During operation it checks the system continuously. After an accident it stores crash data and locks itself, and this state becomes visible via the warning light.

Why does the control unit C1BT-14B321-AC fail?

The most common cause on the C1BT-14B321-AC is crash data stored after an accident, even if no airbag has deployed. Other causes are ageing components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

An ordinary diagnostic tool cannot remove crash data. The fault therefore remains even after reading out. Airbag24 clears the crash data as part of the repair.

Ageing components and solder joints that have stayed cold affect the electronics over years. Moisture and corrosion weaken plug connections, and voltage spikes from a weak battery or a jump start add further stress. The fault memory shows the specific cause.

How can you tell that the C1BT-14B321-AC is defective?

A defect in the C1BT-14B321-AC shows as the airbag warning light in the instrument cluster lighting up permanently or intermittently, as an error message there, as a diagnostic tool without connection to the control unit, or as a fault memory entry that cannot be cleared.

Typical signs at a glance:

• Airbag warning light, lit permanently or intermittently
• Error message in the instrument cluster
• Diagnostic tool that cannot connect to the control unit
• Fault memory entry that cannot be cleared

With these signs, airbags and seatbelt pretensioners may not be able to deploy in an emergency. Please have the finding checked promptly.

Which vehicles is the C1BT-14B321-AC fitted in?

The control unit C1BT-14B321-AC is fitted in these vehicles: Ford Fiesta 7 ’09 (2008-2017).

The list below shows which vehicles belong to this part number.

• Ford Fiesta 7 ’09 (2008-2017)

Compare the part number on the label of the removed unit with this page, and you will know that it is the correct unit. The fault memory result gives different information: it shows whether the control unit is defective or whether a plug or cable is the cause. Therefore have the fault memory read out before removal.

For the same vehicles, we also repair control units with the part numbers C1BT-14B321-CF, H1BT-14B321-AH, H1BT-14B321-AJ.

How does the repair of the C1BT-14B321-AC work?

First have the fault memory of the C1BT-14B321-AC read out and enclose the log, then disconnect the battery and only then remove the C1BT-14B321-AC. Afterwards you create the repair order online and send the unit in well packed. At Airbag24, checking, repairing and testing usually take 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components, clears stored crash data and carries out a function test.

Your own unit is then returned to you. 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 C1BT-14B321-AC get to Airbag24?

You send the control unit C1BT-14B321-AC to us as a parcel, or book a UPS collection for an extra charge. After the repair UPS brings the unit back to you from Airbag24.

Pack the printed repair order into the parcel and pack the control unit shock-resistant.