Airbag control unit with part number 77960-TGH-E820-M4

What does the airbag control unit 77960-TGH-E820-M4 do?

The airbag control unit 77960-TGH-E820-M4 is the central control unit of the restraint system (SRS) for Honda. It checks the crash sensors, decides in an accident within milliseconds on the triggering of airbags and seatbelt pretensioners, and monitors the system continuously. It reports faults via the airbag warning light.

While the vehicle is in operation, the unit works constantly in the background. Deviations are stored in the fault memory so that they can be traced later.

After an accident, the unit stores crash data and locks itself. It is the repair that lifts this lock.

Why does the control unit 77960-TGH-E820-M4 fail?

The most common cause: crash data stored after an accident, even if no airbag was triggered. A normal diagnostic tool cannot delete it. Other causes include aged components, cold solder joints, moisture and corrosion, and voltage spikes.

Stored crash data is therefore possible even when the airbags have remained untouched.

The other causes develop over a longer period. Moisture at plug connections first causes dropouts, and a weak battery or a jump start can produce voltage spikes that attack components.

How can you tell that the 77960-TGH-E820-M4 is defective?

The airbag warning light in the instrument cluster lights up permanently or intermittently. An error message accompanies it, and the diagnostic tool cannot connect to the control unit. In addition, the fault memory cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may not trigger in the event of a defect. Please have the warning checked promptly.

The warning light is a direct signal from the system about the fault.

Which vehicles is the 77960-TGH-E820-M4 fitted in?

The 77960-TGH-E820-M4 is fitted in these vehicles for Honda: Honda Civic 10th generation (2015-2022).

The vehicles are listed in the following overview:

• Honda Civic 10th generation (2015-2022)

First compare the part number on the label of the removed unit with this page; this only ensures that it is the right unit. Additionally, have the fault memory read out beforehand, because only this result shows whether the control unit is defective or whether a connector or a cable is the cause.

For the same vehicles, we also repair control units with the part numbers 77960-3A2-A810-M2, 77960-3A2-A820-M2, 77960-3A2-A830-M2, 77960-TBA-A01, 77960-TBA-A02, 77960-TBA-A03.

How does the repair of the 77960-TGH-E820-M4 work?

First have the fault memory read out and attach the log. Only then disconnect the battery and remove the control unit. Next, create a repair order online and send in the unit, well packed. At Airbag24, processing usually takes 3–4 working days.

Airbag24 checks the unit on the test bench, replaces defective components, deletes stored crash data and carries out a function test. Afterwards your own unit goes 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-TGH-E820-M4 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 it back to you by UPS.

Put the printed repair order into the parcel and pack the control unit so that it is shock-resistant.