Airbag control unit with part number 77960-TWB-B210-M4

What does the airbag control unit 77960-TWB-B210-M4 do?

The airbag control unit 77960-TWB-B210-M4 controls the restraint system (SRS) for Honda. It evaluates the signals from the crash sensors, decides within milliseconds in a crash whether airbags and seatbelt pretensioners are triggered, and monitors the system continuously. It shows faults via the airbag warning light; after a crash, it stores crash data and locks itself.

Monitoring continues in the background between journeys. The unit checks sensors, wiring and output stages and records every deviation in the fault memory.

As long as the system works without faults, the warning light stays off. It only lights up once the unit has detected a fault.

Why does the control unit 77960-TWB-B210-M4 fail?

The most common cause is crash data stored after an accident, even if no airbag was triggered. Other causes are aged electronic components, cold solder joints, moisture and corrosion at connectors, and voltage spikes, for example from a weak battery or jump-starting.

Crash data are records that the unit creates after an accident. A normal diagnostic tool cannot delete them. Airbag24 deletes them during the repair.

Electronic components age, and solder joints can turn cold and unreliable over time. Moisture and corrosion attack the contacts of connectors, while voltage spikes add further strain to the electronics.

How can you tell that the 77960-TWB-B210-M4 is defective?

The airbag warning light in the instrument cluster is on permanently or intermittently, an error message appears in the instrument cluster, the diagnostic tool finds no connection to the control unit, and the fault memory cannot be cleared.

The warning light is the most visible sign of a fault, so when it lights up it needs prompt checking.

In an emergency, airbags and seatbelt pretensioners may not trigger in the event of a defect. An early finding is therefore the better starting point for the repair.

Which vehicles is the 77960-TWB-B210-M4 fitted in?

The control unit 77960-TWB-B210-M4 is fitted in these vehicles: Honda Accord 10th generation (2017-2024).

The matching models are listed individually below.

• Honda Accord 10th generation (2017-2024)

Compare the part number on the label of the removed unit with this page, so you can be sure it is the right unit. Also have the fault memory read out in advance, because only that result shows whether the control unit is defective or whether a connector or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 77960-T3L-A012-M1, 77960-T3L-C012-M4, 77960-T3L-C020-M4, 77960-T3L-C030-M4, 77960-T3L-F012-M4, 77960-T3L-F020-M4.

How does the repair of the 77960-TWB-B210-M4 work?

First have the fault memory read out and enclose the log. Then disconnect the battery, remove the control unit and create a repair order online. Then send in the well-packed unit. Checking, repairing and testing at Airbag24 usually take 3–4 working days.

The sequence protects you while work is carried out on the vehicle. The control unit is removed only after the battery has been disconnected.

Airbag24 checks the unit on the test bench, replaces defective components, deletes the crash data and runs a function test. Afterwards your own unit is returned 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-TWB-B210-M4 get to Airbag24?

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

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