Airbag control unit with part number 77960-T3L-F020-M4

What does the airbag control unit 77960-T3L-F020-M4 do?

The airbag control unit 77960-T3L-F020-M4 controls the restraint system (SRS) for Honda. It processes the readings from the crash sensors, decides in the event of a crash within milliseconds which airbags and seatbelt pretensioners fire, and checks the system continuously.

Faults in the system appear as a warning via the airbag warning light in the instrument cluster. At the same time they are stored in the fault memory, where they can be read out later.

After an accident the control unit records crash data and then locks itself. This very state makes it so important to clarify the fault early.

Why does the control unit 77960-T3L-F020-M4 fail?

Most often the cause is crash data stored after an accident, even if no airbag has deployed. This data cannot be cleared with an ordinary diagnostic tool, so the fault remains.

For the remaining causes, it is mostly ageing electronics. Aged components on the circuit board, cold solder joints, moisture, and corrosion on plug connections can impair function. Voltage spikes, for example from a weakened battery or when connecting a jump-start, also place a load on the unit.

Which of these reasons applies to your unit can only be established by examination on the test bench.

How can you tell that the 77960-T3L-F020-M4 is defective?

Typical signs are an airbag warning light in the instrument cluster that stays on permanently or intermittently, a fault message there, a lack of connection to the diagnostic tool, and a fault memory that cannot be cleared.

The airbag warning light in the instrument cluster is usually the first sign. If it lights only occasionally, take it just as seriously as permanent lighting.

If airbags and seatbelt pretensioners may possibly not deploy in an emergency, that is a risk you should not underestimate.

Which vehicles is the 77960-T3L-F020-M4 fitted in?

The control unit 77960-T3L-F020-M4 is fitted in these vehicles: Honda Accord 10th generation (2017-2024) and 11th generation (from 2023).

The list at a glance:

• Honda Accord 10th generation (2017-2024)
• Honda Accord 11th generation (from 2023)

Before you remove the unit, have the fault memory read out. Only then do you know for certain whether the control unit itself is defective and not a plug or cable. Afterwards compare the part number on the label of the removed unit with this page.

For the same vehicles, we also repair control units with the part numbers 77960-SDA-L814-M1, 77960-T3L-A012-M1, 77960-T3L-A01M1.

How does the repair of the 77960-T3L-F020-M4 work?

At Airbag24, testing, repairing and checking the unit usually take 3–4 working days. Your tasks beforehand are reading out the fault memory, removing the unit and sending it in with an online repair order.

Have the fault memory read out before removal and enclose the log. Disconnect the battery, remove the control unit 77960-T3L-F020-M4, and create the repair order online. Then pack the unit carefully.

Airbag24 examines the unit on the test bench, replaces defective components, clears stored crash data and carries out a function test. The unit then returns 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-T3L-F020-M4 get to Airbag24?

You either send the unit as a parcel or arrange a UPS collection for an extra charge. The return after the repair is also by UPS.

Enclose the printed repair order in the parcel, and pack the control unit 77960-T3L-F020-M4 shock-resistant so nothing is damaged.