Airbag control unit with part number 77960-T2A-N021-M1

What does the airbag control unit 77960-T2A-N021-M1 do?

The unit 77960-T2A-N021-M1 acts as the airbag control unit and controls the restraint system (SRS) of Honda. At the moment of a crash, it evaluates the sensor signals and decides within milliseconds whether airbags and seatbelt pretensioners are triggered. After an accident, it stores crash data and locks itself; only the repair lifts the lock.

It also monitors the connected components continuously and indicates faults via the airbag warning light.

Why does the control unit 77960-T2A-N021-M1 fail?

Most often the cause is crash data stored after an accident, even if no airbag was deployed, and an ordinary diagnostic tool cannot erase it. Other causes include aged electronic components, cold solder joints, moisture or corrosion at plug connections, and voltage spikes, which can occur for example when starting with external power.

Crash data is information about the accident stored in memory, not a component you could see. It does affect how the system works, which is why it is an obvious point to check.

The other causes can only be narrowed down by testing.

How can you tell that the 77960-T2A-N021-M1 is defective?

A fault shows up via the airbag warning light, which stays on or flickers, and via error messages in the instrument cluster. Airbags and seatbelt pretensioners may not deploy in a real crash while such a fault persists.

In detail, these signs stand out:

• The airbag warning light in the instrument cluster stays on or flickers
• An error message in the instrument cluster
• The diagnostic tool finds no connection to the control unit
• The fault memory cannot be cleared

If the warning light stays on, have the system checked promptly.

Which vehicles is the 77960-T2A-N021-M1 fitted in?

The airbag control unit 77960-T2A-N021-M1 is fitted in these vehicles: Honda CR-V 4 RM (2012-2018).

The vehicles for which this part number is stored are listed here:

• Honda CR-V 4 RM (2012-2018)

Before sending it in, compare the part number on the label of the removed unit with this page. This only confirms that it is the correct unit. Also have the fault memory read out; only this result shows whether the control unit itself 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-T0A-3070-M4, 77960-T0A-A012-M1, 77960-T0A-A013-M1, 77960-T0A-A210-M1, 77960-T0A-A212-M1, 77960-T0A-A230-M1.

How does the repair of the 77960-T2A-N021-M1 work?

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

At Airbag24, the test bench checks the unit first. Defective components are then replaced, the stored crash data is erased and a function test is carried out, after which your own unit goes back to you. Processing at Airbag24 generally takes 3–4 working days, and this period covers only checking, repairing and testing.

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-N021-M1 get to Airbag24?

You send the unit in as a parcel, or book a UPS collection for an extra charge. After the repair, Airbag24 sends the unit back to you by UPS.

Put the printed repair order into the parcel and pack the unit shock-proof.