Airbag control unit with part number 77960-TLA-A250-M4

What does the airbag control unit 77960-TLA-A250-M4 do?

The airbag control unit 77960-TLA-A250-M4 is the central control unit of the restraint system (SRS) of Honda. It reads the signals from the crash sensors, decides within milliseconds in an accident which airbags and seatbelt pretensioners are triggered, and monitors the system continuously. It shows faults via the airbag warning light.

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

While driving, it constantly checks sensors and wiring. It records irregularities in the fault memory so that they can be read out later.

Why does the control unit 77960-TLA-A250-M4 fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed. Other causes include ageing electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes such as those from a weak battery or a jump start.

Crash data cannot be removed with a standard diagnostic tool. Airbag24 erases it during the repair.

The workshop checks the other causes on the unit itself, because they cannot be identified from the outside.

How can you tell that the 77960-TLA-A250-M4 is defective?

The airbag warning light in the instrument cluster stays on constantly or intermittently, an error message appears in the instrument cluster, the diagnostic tool finds no connection to the control unit, or the fault memory cannot be cleared. With any of these signs, airbags and seatbelt pretensioners may fail to deploy in an emergency.

The warning light is usually the first thing noticed in the car. If it does not go dark after starting, it is worth reading the fault memory with a suitable tool or having a workshop do it.

A warning in the instrument cluster should therefore be taken seriously, even if the vehicle otherwise seems to run normally.

Which vehicles is the 77960-TLA-A250-M4 fitted in?

The control unit 77960-TLA-A250-M4 is fitted in these vehicles: Honda CR-V 5 (2018-2023).

The stored assignment follows here:

• Honda CR-V 5 (2018-2023)

Before removal, the following steps make sense: compare the part number on the label of the removed unit with this page, which only confirms that it is the right unit. Also have the fault memory read out beforehand, because only this result shows whether the control unit is defective or whether a plug or a cable is the cause.

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-A250-M4 work?

First, have the fault memory read out and enclose the log with the package. Then disconnect the battery, and only now remove the control unit 77960-TLA-A250-M4. Afterwards, create a repair order online and send the unit in well packed.

Airbag24 checks the unit that has been sent in on the test bench and repairs defective components. Stored crash data is erased, followed by a function test. The unit then goes back to you. Processing at Airbag24 usually takes 3–4 working days.

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-A250-M4 get to Airbag24?

Either you send the unit as a parcel, or you book a UPS collection for an extra charge. Airbag24 returns it by UPS after the repair.

Enclose the printed repair order in the parcel, and pack the control unit shockproof.