Airbag control unit with part number 77960-TWC-H230-M4

What does the airbag control unit 77960-TWC-H230-M4 do?

The 77960-TWC-H230-M4 is the airbag control unit for the SRS restraint system of Honda. It continuously checks the signals from the crash sensors and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners are triggered.

The system monitors itself permanently. If it detects a fault, it shows this via the airbag warning light in the instrument cluster.

After an accident, the control unit stores crash data and locks itself.

Why does the control unit 77960-TWC-H230-M4 fail?

The most common cause is crash data stored after an accident, even if no airbag fired. Other causes include ageing components, cold solder joints, moisture or corrosion on plug connections, and voltage spikes, for example from a weak battery or a jump start.

Crash data remains in the control unit, and a normal diagnostic tool cannot erase it. That is why it plays a central role in fault finding.

In addition, age-related damage to components, cold solder joints, and moisture or rust on the plugs can occur. Voltage spikes from the vehicle's electrical system can also strain the unit.

How can you tell that the 77960-TWC-H230-M4 is defective?

A fault shows itself through the airbag warning light in the instrument cluster, which lights up permanently or intermittently, and through an error message in the display. Likewise, the diagnostic tool may be unable to connect to the control unit, or the fault memory cannot be cleared.

These signs at a glance:

• Airbag warning light, permanently or intermittently
• Error message in the instrument cluster
• Diagnostic tool without connection to the control unit
• Fault memory cannot be cleared

As long as these signs persist, airbags and seatbelt pretensioners may not deploy in an emergency.

Which vehicles is the 77960-TWC-H230-M4 fitted in?

The 77960-TWC-H230-M4 is fitted in these vehicles: Honda Accord 10th generation (2017-2024).

The list for this part number:

• Honda Accord 10th generation (2017-2024)

Compare the number on the label of the removed unit with this page, then you know you have the right unit. The fault memory clarifies the cause: have it read out before removal, and it will show whether the control unit is defective or whether a plug or a 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-TWC-H230-M4 work?

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

At Airbag24 the unit is checked on the test bench, defective components are replaced, the stored crash data is erased and a function test is carried out. Your own unit is then returned to you.

Processing at Airbag24 usually takes 3–4 working days. 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-TWC-H230-M4 get to Airbag24?

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

Put the printed repair order in the parcel, and pack the unit securely against impact.