Airbag control unit with part number 77960-TWB-H040-M4

What does the airbag control unit 77960-TWB-H040-M4 do?

The airbag control unit 77960-TWB-H040-M4 processes the sensor data in the restraint system (SRS) of Honda. In the event of an impact, it determines within milliseconds how the airbags and seatbelt pretensioners are triggered and monitors the system permanently.

Every fault it detects is reported via the airbag warning light in the instrument cluster. This keeps the state of the system traceable, even for a later workshop.

If an accident occurs, the unit stores crash data and locks itself. The workshop finds this state first.

Why does the control unit 77960-TWB-H040-M4 fail?

Most often the cause is crash data stored after an accident, even if no airbag has deployed. Further causes are ageing, cold solder joints, moisture and voltage spikes.

A normal diagnostic tool cannot clear the data; Airbag24 does this during the repair. The other causes at a glance:

• aged electronic components
• cold solder joints
• corrosion and moisture at plug connections
• voltage spikes in the vehicle electrical system

How can you tell that the 77960-TWB-H040-M4 is defective?

The airbag warning light in the instrument cluster comes on permanently or intermittently, and a fault message appears alongside it. In addition, no connection to the diagnostic tool can be established, and the fault memory cannot be cleared. The airbags and seatbelt pretensioners may then not deploy in an emergency.

A warning light that stays on calls for a check, even if the vehicle can still be driven normally. If you ignore the warning, the cause remains unclear.

Only the fault memory shows whether the control unit itself is affected. A missing connection may also be due to a plug or a cable, so only reading out the fault memory will help.

Which vehicles is the 77960-TWB-H040-M4 fitted in?

Compare your car with the list that follows. The airbag control unit 77960-TWB-H040-M4 is fitted in these vehicles: Honda Accord 10th generation (2017-2024).

In detail, these are the vehicles as they are recorded in our data for this part number.

• Honda Accord 10th generation (2017-2024)

Even before removal, it is worth looking at the label. Comparing the label with this page only shows that the matching unit is in front of you. Having the fault memory read out is the step that 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-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-H040-M4 work?

First the fault memory is read out, and the log travels with the unit; only then do you disconnect the battery and remove the control unit. Online you create the repair order and send the unit in well packed. Processing at Airbag24 usually takes 3–4 working days for checking, repairing and testing.

On the test bench the unit is examined, then defective components are replaced, the crash data is deleted and a function test is run. 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-H040-M4 get to Airbag24?

You send the unit as a parcel, or for an extra charge you book a UPS collection. The unit comes back to you by UPS after the repair.

Put the printed repair order into the parcel and pack the unit shockproof.