Airbag control unit with part number 77960-TF0-Y421-M3

What does the airbag control unit 77960-TF0-Y421-M3 do?

The airbag control unit 77960-TF0-Y421-M3 is the central control unit of the restraint system (SRS) for Honda. It evaluates the crash sensors, decides within milliseconds in a crash on airbags and seatbelt pretensioners, and monitors the system continuously.

Faults are indicated by the unit via the airbag warning light in the instrument cluster. After a crash it stores crash data and locks itself. The lock is only lifted by a repair.

Why does the control unit 77960-TF0-Y421-M3 fail?

The most common cause of a failure of the 77960-TF0-Y421-M3 is crash data stored after an accident, even if no airbag was triggered. Other causes in overview:

A standard diagnostic tool cannot erase the crash data. Airbag24 erases it during the repair.

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

How can you tell that the 77960-TF0-Y421-M3 is defective?

A defect on the 77960-TF0-Y421-M3 shows up in the airbag warning light, which lights up permanently or intermittently, in a fault message in the instrument cluster, in a diagnostic tool without a connection, and in a fault memory that cannot be cleared.

• The airbag warning light lights up permanently or intermittently.
• The instrument cluster displays a fault message.
• The diagnostic tool cannot find the control unit.
• The fault memory remains even after an attempt to clear it.

In that case airbags and seatbelt pretensioners may possibly not trigger in a crash. The warning light makes the defect visible, so have it checked promptly.

Which vehicles is the 77960-TF0-Y421-M3 fitted in?

The 77960-TF0-Y421-M3 is fitted in several models by Honda. It is fitted in these vehicles: Honda Jazz GE (2008-2015).

The assigned models are listed here:

• Honda Jazz GE (2008-2015)

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

For the same vehicles, we also repair control units with the part numbers 5WK43461, 77960-SAA-G821-M1, 77960-SEG-G821-M1, 77960-TF0-G820-M3, 77960-TF0-G821.

How does the repair of the 77960-TF0-Y421-M3 work?

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

Airbag24 checks the unit on the test bench, replaces defective components, erases stored crash data and carries out a function test. Afterwards your own unit 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 77960-TF0-Y421-M3 get to Airbag24?

You send the 77960-TF0-Y421-M3 as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends the unit back to you by UPS.

Enclose the printed repair order in the parcel and pack the control unit shock-proof.