Airbag control unit with part number 77960-TVA-S020-M4

What does the airbag control unit 77960-TVA-S020-M4 do?

For Honda, the airbag control unit 77960-TVA-S020-M4 controls the restraint system (SRS). It monitors the crash sensors and decides in a crash, within milliseconds, which airbags and seatbelt pretensioners trigger. If an accident has occurred, crash data are stored and the unit locks itself.

The unit's continuous operation covers checking all sensors and wiring of the system. If it detects a deviation, the airbag warning light in the instrument cluster lights up.

The decision on triggering is therefore not made only in an accident; it rests on constant readiness.

Why does the control unit 77960-TVA-S020-M4 fail?

Crash data stored after an accident are the most common cause with the 77960-TVA-S020-M4, even if no airbag has deployed. They cannot be deleted with a normal diagnostic tool. Other possible causes are aged components, cold solder joints, moisture and corrosion on plugs, and voltage spikes.

The crash data are generated in the unit itself; the memory holds them.

The remaining causes stay general. Electronic components age, solder joints can lose contact, and moisture or corrosion disturb the connections. Voltage spikes, for example from a weak battery or jump-starting, also stress the electronics.

How can you tell that the 77960-TVA-S020-M4 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently on the 77960-TVA-S020-M4. A fault message also appears, the diagnostic tool cannot find the control unit, and the fault memory remains unchanged because it cannot be cleared.

The warning light is the system's own direct feedback, so it must be taken seriously.

While the fault persists, airbags and seatbelt pretensioners may not trigger in an emergency. Have the finding checked promptly.

Which vehicles is the 77960-TVA-S020-M4 fitted in?

A look at the allocation shows which models the number fits. The control unit 77960-TVA-S020-M4 is fitted in these vehicles: Honda Accord 10th generation (2017-2024).

The vehicles on this list:

• Honda Accord 10th generation (2017-2024)

Start with the label comparison: the part number on the removed unit is compared with this page, and this only confirms the correct unit. Then have the fault memory read out, because only this result 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-TVA-S020-M4 work?

First have the fault memory read out and attach the log, then disconnect the battery and only then remove the control unit 77960-TVA-S020-M4. Afterwards create a repair order online and send in the well-packed unit. Processing at Airbag24 usually takes 3–4 working days.

At Airbag24 the unit is checked, defective components are repaired, the stored crash data are deleted, and a function test concludes the work. Afterwards your own unit comes back 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-TVA-S020-M4 get to Airbag24?

You send the control unit 77960-TVA-S020-M4 as a parcel, or you book a UPS collection for an extra charge. Airbag24 sends it back by UPS after the repair.

The unit must be packed shock-resistant, and the printed repair order goes in with it.