Airbag control unit with part number 77960-SJA-L040-M2

What does the airbag control unit 77960-SJA-L040-M2 do?

The SRS control unit 77960-SJA-L040-M2 is the airbag control unit for Honda. It keeps the restraint system operational, checks the sensors and decides in a collision which airbags and seatbelt pretensioners are triggered. This takes only milliseconds.

While driving, it monitors the system without interruption. It indicates faults via the airbag warning light in the instrument cluster.

An accident leads to crash data being stored, and after that the control unit locks itself.

Why does the control unit 77960-SJA-L040-M2 fail?

Crash data from an accident is the most common cause in the control unit 77960-SJA-L040-M2, even if no airbag was triggered. An ordinary diagnostic tool does not make it disappear. Aged components, cold solder joints, moisture at plug connectors and voltage spikes are also possible causes.

The crash data is held in the memory of the control unit. Airbag24 removes it during the repair.

Independently of this, electronic components can deteriorate over time. Solder joints can go cold, and moisture leads to corrosion at plug connectors.

Voltage spikes, for example from a weak battery or when a jump start is connected, additionally stress the unit.

How can you tell that the 77960-SJA-L040-M2 is defective?

An airbag warning light in the instrument cluster that lights up permanently or intermittently indicates the fault in the 77960-SJA-L040-M2. It is accompanied by an error message. In this case, airbags and seatbelt pretensioners may possibly not trigger in an emergency.

In addition, there is a diagnostic tool that cannot establish a connection to the control unit, and a fault memory that cannot be cleared. Both findings call for the system to be checked.

The warning light is the clearest signal, so react promptly.

Which vehicles is the 77960-SJA-L040-M2 fitted in?

The control unit 77960-SJA-L040-M2 is fitted in the following vehicles: Honda Legend 4th generation (2004-2012).

The list of individual vehicles follows here:

• Honda Legend 4th generation (2004-2012)

Compare the part number on the removed unit with this page. This only confirms that you have the matching unit in front of you, nothing more. Whether the control unit itself is defective or a plug or cable is the cause is clarified by the fault memory read-out beforehand.

For the same vehicles, we also repair control units with the part numbers 77960-S3V-C11, 77960-SJV-A94, 77960-SWV-A94.

How does the repair of the 77960-SJA-L040-M2 work?

First have the fault memory read out and enclose the log with the unit. Then disconnect the battery and remove the control unit 77960-SJA-L040-M2. Afterwards create a repair order online and send the packed unit.

At Airbag24 the unit is inspected, defective components are replaced, the crash data is deleted, and a function test follows. Then your own unit comes back to you.

For inspection, repair and testing at Airbag24, allow 3–4 working days as a rule. This time excludes both removal and shipping.

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-SJA-L040-M2 get to Airbag24?

You send the control unit 77960-SJA-L040-M2 yourself as a parcel, or you book a UPS collection for an extra charge. Airbag24 handles the return of the repaired unit with UPS.

Pack the unit shock-proof and enclose the printed repair order.