Airbag control unit with part number 77960-T70-H020-M4

What does the airbag control unit 77960-T70-H020-M4 do?

The 77960-T70-H020-M4 controls the restraint system (SRS) of Honda. It detects an accident through its sensors and decides within fractions of a second which airbags and seatbelt pretensioners are triggered. In addition it monitors all components and shows faults via the airbag warning light.

The unit runs in the background and checks the connections to the sensors, airbags and seatbelt pretensioners. It stores detected deviations and makes them visible via the warning light.

After an accident the unit stores crash data and locks itself. Only a repair lifts the lock.

Why does the control unit 77960-T70-H020-M4 fail?

The most common cause is stored crash data, even if no airbag triggered in the accident. A standard diagnostic tool cannot erase it. Further causes include aged components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Crash data remains in the unit even if the vehicle continues to drive normally afterwards. That it runs normally therefore does not mean that no data is stored.

The other causes lie in the electronics and their connections. Solder joints can go cold, components age, and moisture causes corrosion on contacts. A weak battery or a jump start can also produce voltage spikes.

How can you tell that the 77960-T70-H020-M4 is defective?

The airbag warning light in the instrument cluster stays on permanently or intermittently, or a fault message appears in the instrument cluster. The diagnostic tool then finds no connection to the control unit, or the fault memory cannot be cleared. In an emergency, airbags and seatbelt pretensioners may then fail to trigger.

These signs are a clear reason to have the system checked. The warning light is the most visible hint.

Even a fault that occurs only intermittently is recorded in the fault memory and deserves a read-out.

Which vehicles is the 77960-T70-H020-M4 fitted in?

Whether the vehicle fits, you can see in the list. The 77960-T70-H020-M4 is fitted in these vehicles: Honda HR-V 2nd generation (2015-2022).

The vehicles known for this part number are listed here:

• Honda HR-V 2nd generation (2015-2022)

If the part number on the label of the removed unit matches this page, only the right unit is confirmed. Whether the control unit is defective or a plug or cable is the cause only shows in the fault memory read out beforehand.

For the same vehicles, we also repair control units with the part numbers 77960-3V0-A81, 77960-T7S-A21, 77960-T7S-A212-M2, 77960T7SK410M2.

How does the repair of the 77960-T70-H020-M4 work?

Airbag24 needs 3–4 working days as a rule for checking, repairing and testing. Before removal, read out the fault memory, remove the control unit and create the repair order online.

Enclose the log of the fault memory, disconnect the battery and pack the unit well before sending it in. Airbag24 checks the unit on the test bench, replaces defective components, erases the crash data and carries out a function test. Your unit then 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-T70-H020-M4 get to Airbag24?

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

Put the printed repair order into the parcel, and pack the control unit shock-proof.