Airbag control unit with part number 77960-T2V-R020-M4

What does the airbag control unit 77960-T2V-R020-M4 do?

The airbag control unit 77960-T2V-R020-M4 forms the switching point for airbags and seatbelt pretensioners in the SRS restraint system of Honda. It processes the sensor signals, selects in a crash within milliseconds the triggering, and checks the system continuously. After an accident, it writes crash data and then goes into a locked state.

The crash sensors supply acceleration values to the unit, which assesses them according to fixed rules. The selection of the restraint devices takes place within a fraction of a second.

During ongoing operation, the unit monitors its connections and igniters. If it detects a fault, it reports it via the airbag warning light.

Why does the control unit 77960-T2V-R020-M4 fail?

The most common cause is an entry in the crash data from an earlier accident, even if no airbag was triggered in it. An ordinary diagnostic tool cannot remove it. In addition come aged components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

That the data cannot be removed with a standard diagnostic tool explains why the fault persists even though nothing conspicuous can be seen on the vehicle.

The other triggers are ageing of the electronics, poor contacts caused by moisture or corrosion, and voltage spikes, for example from a weak battery or a jump-start.

How can you tell that the 77960-T2V-R020-M4 is defective?

On the 77960-T2V-R020-M4, a defect shows up as an airbag warning light in the instrument cluster that lights up permanently or intermittently. In addition, a fault message appears in the instrument cluster, the diagnostic tool finds no connection, and the fault memory cannot be cleared.

A warning signal of this kind requires a prompt check.

In an emergency, airbags and seatbelt pretensioners may then possibly fail to trigger. If the indication is ignored, the restraint system may be operating in a limited way.

Which vehicles is the 77960-T2V-R020-M4 fitted in?

The control unit 77960-T2V-R020-M4 is fitted in these vehicles: Honda Accord 9th generation (2012-2019).

The models that belong to this part number are listed here:

• Honda Accord 9th generation (2012-2019)

Compare the part number on the label of the removed control unit with this page in advance. This alone clarifies whether it is the right unit. Also have the fault memory read out before you take any action: only this log 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-SEA-G815-M1, 77960-T3L-A012-M1, C0W6K4VDA.

How does the repair of the 77960-T2V-R020-M4 work?

For the 77960-T2V-R020-M4, first have the fault memory read out and enclose the log, then disconnect the battery and remove the control unit. Next, create a repair order online and send the unit in well packed. For testing, repairing and the function test at Airbag24, 3–4 working days are usually planned.

At Airbag24 the unit is checked first, and then defective components are specifically renewed. The stored crash data is erased by the team, followed by a function test. Afterwards, your own unit is returned 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-T2V-R020-M4 get to Airbag24?

You send the control unit 77960-T2V-R020-M4 as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 sends it back to you by UPS.

Place the printed repair order in the parcel and pack the unit shock-proof.