Airbag control unit with part number 3F900-80T00

What does the airbag control unit 3F900-80T00 do?

The airbag control unit 3F900-80T00 coordinates the restraint system (SRS) in Suzuki vehicles. It analyses the signals from the crash sensors, determines within milliseconds in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. After an accident it stores crash data and locks itself.

It reports faults via the airbag warning light in the instrument cluster. Monitoring takes place without interruption during operation.

Without an intact control unit, the restraint system cannot work as intended in an emergency.

Why does the control unit 3F900-80T00 fail?

The most common cause is crash data from an accident, even if no airbag was triggered. This data cannot be erased with a normal diagnostic tool. Other causes are ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

This cause only becomes apparent during fault finding, because the crash data stays in the memory.

The other causes:

• ageing electronic components
• cold solder joints
• moisture and corrosion at plug connections
• voltage spikes, for example from a weak battery or a jump start

How can you tell that the 3F900-80T00 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently. Also present are an error message in the instrument cluster, no connection to the diagnostic tool, and a fault memory that cannot be cleared.

These signs reliably indicate a defect. The warning light is the clearest signal you will notice in the vehicle.

In an emergency, airbags and seatbelt pretensioners may fail to trigger. Have the system checked promptly.

Which vehicles is the 3F900-80T00 fitted in?

The airbag control unit 3F900-80T00 is fitted in these vehicles: Suzuki Swift RZ/AZ (2017-2020) and RZ/AZ Facelift (2020-2024).

The vehicles for this part number are listed below:

• Suzuki Swift RZ/AZ (2017-2020)
• Suzuki Swift RZ/AZ Facelift (2020-2024)

Compare the part number on the label of the removed unit with this page. This only shows that you have the correct unit. Have the fault memory read out beforehand, because only this result shows whether the control unit is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 38910-62J12-000, 38SC001R9RH.

How does the repair of the 3F900-80T00 work?

First have the fault memory read out and attach the log. Then disconnect the battery and only then remove the control unit 3F900-80T00. Next, create a repair order online and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days.

At Airbag24 the unit is inspected on the test bench. Defective components are replaced, stored crash data is erased, and then a functional test follows.

The unit then goes back 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 3F900-80T00 get to Airbag24?

You send the control unit 3F900-80T00 as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns it to you by UPS.

Put the printed repair order in the parcel and pack the unit securely against impact.