Airbag control unit with part number 77960-T2A-Y020-M4

What does the airbag control unit 77960-T2A-Y020-M4 do?

The airbag control unit 77960-T2A-Y020-M4 steers the SRS restraint system for Honda. It evaluates the sensor signals, decides in a crash within milliseconds which airbags and seatbelt pretensioners are triggered, and monitors the system continuously.

It reports faults via the airbag warning light in the instrument cluster and records them in the fault memory. This monitoring works in the background.

After an accident it secures crash data and then locks itself.

Why does the control unit 77960-T2A-Y020-M4 fail?

Stored crash data is the most common cause: it remains in the unit after an accident even if no airbag has deployed, and a standard diagnostic tool cannot erase it. Aged components, cold solder joints, moisture and corrosion, and voltage spikes are further possible causes.

The crash data remains in the control unit until Airbag24 removes it during repair. A diagnostic tool does not reach this step.

The other causes concern the electronics and their connections. Components age, solder joints can be unsound, and moisture attacks contacts. Voltage spikes from the vehicle electrical system also load the unit.

How can you tell that the 77960-T2A-Y020-M4 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently, and an error message appears in the instrument cluster. There is also a diagnostic tool without connection to the control unit, and a fault memory that cannot be cleared.

Such signs mean the airbags and seatbelt pretensioners may not trigger in an emergency. The warning light shows the finding as soon as it occurs.

A warning signal in the restraint system should be clarified promptly, even if the vehicle can still be driven normally.

Which vehicles is the 77960-T2A-Y020-M4 fitted in?

The airbag control unit 77960-T2A-Y020-M4 is fitted in these vehicles: Honda Accord 9th generation (2012-2019).

The assignment for this part number can be seen here:

• Honda Accord 9th generation (2012-2019)

First compare the part number on the label of the removed unit with this page. That way you know it is the correct unit. Then have the fault memory read out, because only the log 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 77960-SEA-G815-M1, 77960-T3L-A012-M1, C0W6K4VDA.

How does the repair of the 77960-T2A-Y020-M4 work?

First read out the fault memory and attach the log, then disconnect the battery and remove the control unit. Then create a repair order online, pack the unit well and send it in.

Airbag24 checks the unit on the test bench, repairs defective components, erases the crash data and performs a function test. Afterwards your own unit is returned to you.

Processing at Airbag24 usually takes 3–4 working days. This time relates solely to the work at Airbag24. 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-T2A-Y020-M4 get to Airbag24?

You send the unit 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 shockproof.