Airbag control unit with part number BL84-14B321-AB

What does the airbag control unit BL84-14B321-AB do?

The airbag control unit BL84-14B321-AB is the central control unit of the SRS for Ford. It measures the signals from the impact sensors, decides in an accident within milliseconds whether to trigger the airbags and seatbelt pretensioners, and monitors the entire system.

Faults are indicated by the airbag warning light in the instrument cluster. After an accident it stores crash data and locks itself, and only the repair lifts the lock.

Why does the control unit BL84-14B321-AB fail?

The most common cause is crash data stored after an accident, even without an airbag deployment, which cannot be erased with a normal diagnostic tool. Ageing components, cold solder joints, moisture, corrosion and voltage spikes are also possible causes.

Which cause applies in an individual case is only established by diagnosis:

• Ageing electronic components
• Cold solder joints in the unit
• Moisture and corrosion at plug connections
• Voltage spikes, for example from a weak battery or jump-starting

How can you tell that the BL84-14B321-AB is defective?

A defect in the BL84-14B321-AB first shows up on the airbag warning light in the instrument cluster, which lights up permanently or intermittently. In addition there is an error message in the instrument cluster, no connection between the diagnostic tool and the control unit, and a fault memory that cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may then fail to deploy. A finding like this therefore requires a prompt check.

Which vehicles is the BL84-14B321-AB fitted in?

The BL84-14B321-AB is fitted in these vehicles: Ford Escape 2 (2008-2012).

A list of the assigned vehicles follows:

• Ford Escape 2 (2008-2012)

First check the part number on the label of the removed unit against this page; this only serves as a check that the correct unit is at hand. The fault memory, on the other hand, shows whether the control unit itself is defective or whether a plug or cable is behind it.

For the same vehicles, we also repair control units with the part numbers 8L84-14B321-AG, 8L84-14B321-AH, 8L84-14B321-AJ, 8L84-14B321-AK, 9L84-14B321-AJ, 9L84-14B321-AK.

How does the repair of the BL84-14B321-AB work?

Airbag24 needs 3–4 working days for testing, repair and function test in the normal course. In the process, defective components are repaired and stored crash data is erased.

On your side, you first read out the fault memory with the log enclosed, then disconnect the battery and only then remove the unit. You create the repair order online and send the unit well packed.

After the function test, your own unit is returned. 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 BL84-14B321-AB get to Airbag24?

You send the BL84-14B321-AB as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns the unit by UPS.

Print the repair order, enclose it and pack the control unit shockproof.