Airbag control unit with part number 68400421AB

What does the airbag control unit 68400421AB do?

The airbag control unit 68400421AB is part of the restraint system (SRS) of Jeep and controls it. It evaluates the crash sensors and, in an accident, determines within milliseconds which airbags and seatbelt pretensioners are triggered.

At the same time it monitors the components of the system without interruption. It shows detected faults via the airbag warning light in the instrument cluster.

After an accident the unit stores crash data and locks itself. This lock ends only with the repair.

Why does the control unit 68400421AB fail?

The most frequent cause is crash data stored after an accident, even when no airbag has deployed. Further causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Crash data cannot be removed with an ordinary diagnostic tool; Airbag24 removes it during the repair. The other causes act on the unit over time: electronics age, solder joints can be cold, and moisture attacks the contacts. Voltage spikes arise, for example, from a weak battery or a jump start.

How can you tell that the 68400421AB is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently, a fault message appears in the instrument cluster, or the diagnostic tool finds no connection to the control unit. The fault memory also cannot be cleared. Then airbags and seatbelt pretensioners may not deploy in an emergency.

The warning light is the system's direct indication of a fault. Such a finding requires prompt clarification so that the cause can be checked.

Which vehicles is the 68400421AB fitted in?

The control unit 68400421AB is fitted in these vehicles: Jeep Wrangler JL (from 2018).

The list shows the vehicles for which this control unit is on record.

• Jeep Wrangler JL (from 2018)

Compare the part number on the label of the removed unit with this page, and you will know that it is the right unit. This comparison makes no statement about the condition of the control unit. Therefore have the fault memory read out beforehand, because only the log 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 68398609AB, P68003421AB.

How does the repair of the 68400421AB work?

First you have the fault memory read out and enclose the log. Then you disconnect the battery and only then remove the control unit. Next, you create a repair order online and send in the safely packed unit.

Airbag24 checks the unit on the test bench, replaces defective components, deletes the crash data and carries out a function test. Processing at Airbag24 generally takes 3–4 working days.

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 68400421AB get to Airbag24?

You send the unit to Airbag24 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. Pack the unit shock-proof before sending it.