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

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

The control unit 77960-TGB-H040-M4 is the central control unit of the restraint system (SRS) in Honda. Using the crash sensors, it decides within milliseconds whether and which airbags and seatbelt pretensioners are triggered, and it monitors the entire system.

It also detects faults and shows them via the airbag warning light in the instrument cluster.

If an accident occurs, the unit records crash data and then locks itself.

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

The most common cause with the 77960-TGB-H040-M4 is crash data stored after an accident, even when no airbag was triggered. Other causes include ageing components, cold solder joints, moisture, corrosion and voltage spikes.

Crash data record the event in the unit. An ordinary diagnostic tool cannot remove them. Airbag24 erases them during the repair.

The other causes develop over time: electronic components age, solder joints can remain cold, and moisture or corrosion affect plug connections. Voltage spikes, for example from a weak battery or a jump-start, add further strain.

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

A defect in the 77960-TGB-H040-M4 shows up as the airbag warning light in the instrument cluster, which stays on permanently or intermittently. It is accompanied by an error message in the instrument cluster.

In addition, the fault memory cannot be erased, and a diagnostic tool finds no connection to the control unit.

Such a defect can mean that the airbags and seatbelt pretensioners may not trigger in an emergency. Do not ignore the indication.

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

The 77960-TGB-H040-M4 is fitted in these vehicles: Honda Civic 10th generation (2015-2022).

The assignment is listed here:

• Honda Civic 10th generation (2015-2022)

Comparing the part number on the label of the removed unit with this page only confirms that it is the right unit. Have the fault memory read out beforehand as well, because only it shows whether the control unit itself is defective or whether a plug or cable is the cause.

For the same vehicles, we also repair control units with the part numbers 77960-3A2-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-TGB-H040-M4 work?

The repair of the 77960-TGB-H040-M4 begins with reading out the fault memory, followed by disconnecting the battery and removing the control unit. Processing at Airbag24 usually takes 3–4 working days.

Afterwards you create a repair order online and pack the unit carefully before sending it in. At Airbag24, it is examined on the test bench. Defective components are repaired, the stored crash data are erased and a function test is carried out.

Afterwards your own unit goes back to you. The sequence of removal serves safety in the airbag system. 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-TGB-H040-M4 get to Airbag24?

You can send the control unit 77960-TGB-H040-M4 yourself as a parcel, or have it collected by UPS for an extra charge. Airbag24 sends it back to you by UPS after the repair.

The printed repair order belongs in the parcel. Make sure to pack the unit shock-proof.