Airbag control unit with part number 77960-TLA-J220-M4

What does the airbag control unit 77960-TLA-J220-M4 do?

The 77960-TLA-J220-M4 is the central control unit of the restraint system (SRS) for Honda. It captures the signals from the crash sensors, decides in an emergency within milliseconds on airbags and seatbelt pretensioners, and monitors the entire system.

The unit reports faults via the airbag warning light and keeps them in the fault memory. This keeps the status of the system traceable for the workshop.

After an accident the unit stores crash data and locks itself. Every diagnosis establishes this first.

Why does the control unit 77960-TLA-J220-M4 fail?

The most common cause is stored crash data after an accident, even if no airbag has fired; a normal diagnostic tool cannot erase it. Further causes are aged components, cold solder joints, moisture and corrosion, and voltage spikes.

Stored crash data is the cause that occurs most often. It remains in memory even if no airbag fired. Airbag24 erases it during the repair.

The other causes are fairly everyday: electronics age, solder joints can go cold, and moisture together with corrosion impairs the plug connections. Voltage spikes, for example from a weak battery, additionally strain the unit.

How can you tell that the 77960-TLA-J220-M4 is defective?

The airbag warning light in the instrument cluster lights up continuously or intermittently, a fault message appears in the instrument cluster, the diagnostic tool 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 deploy.

The light is the clearest sign you see in the vehicle. It becomes active as soon as the unit detects a fault, and it should therefore be taken seriously.

If the diagnostic tool cannot establish a connection, or the fault memory cannot be cleared, an early read-out is worthwhile. Only then does it become clear what the cause is.

Which vehicles is the 77960-TLA-J220-M4 fitted in?

The 77960-TLA-J220-M4 is fitted in these vehicles: Honda CR-V 5 (2018-2023).

The following overview lists the vehicles recorded for this part number.

• Honda CR-V 5 (2018-2023)

Please note the following. Compare the part number on the label of the removed unit with this page; this only confirms that it is the correct unit. Also have the fault memory read out beforehand, because the result shows whether the control unit is the cause or whether a plug or cable is behind it.

For the same vehicles, we also repair control units with the part numbers 5WK43782, 77960-SWA-G212-M4, 77960-SWA-G214-M4, 77960-SWAA-213-M1.

How does the repair of the 77960-TLA-J220-M4 work?

First have the fault memory read out and enclose the log, then disconnect the battery and only then remove the 77960-TLA-J220-M4. Then create the repair order online and send in the well-packed unit. Processing at Airbag24 usually takes 3–4 working days.

The first steps are for your safety during removal. The log in the parcel makes checking easier, because the finding is present from the start.

After the functional test 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-TLA-J220-M4 get to Airbag24?

You send the 77960-TLA-J220-M4 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 unit shock-proof.