Airbag control unit with part number 77960-TAA-J513-M4

What does the airbag control unit 77960-TAA-J513-M4 do?

The airbag control unit 77960-TAA-J513-M4 forms the control centre of the SRS restraint system in Honda vehicles. The crash sensors report accelerations to it, and in an impact it decides within a fraction of a second which airbags and seatbelt pretensioners are triggered.

During operation, it checks the system continuously. Any faults it finds are shown via the airbag warning light.

After an accident, the unit creates crash data and locks itself. The lock ends only with the repair.

Why does the control unit 77960-TAA-J513-M4 fail?

The most common cause is crash data stored after an accident, even when the airbags did not trigger; a normal diagnostic tool does not delete it. Other causes include aged components, cold solder joints, moisture and corrosion, and voltage spikes at the 77960-TAA-J513-M4.

The data remains stored in the unit until it is removed during a repair. Simply reading out the fault memory does not remove the cause.

The remaining causes are rather general. Electronic components wear out over time, solder joints can become cold, and moisture or corrosion at plugs disrupts the connection. A weak battery or a jump-start can also cause the voltage to fluctuate strongly for a short time.

How can you tell that the 77960-TAA-J513-M4 is defective?

A defect in the 77960-TAA-J513-M4 becomes visible through the airbag warning light in the instrument cluster, which lights up permanently or only intermittently. Error messages in the instrument cluster, a missing connection to the diagnostic tool and a fault memory that cannot be cleared are further signs.

With such a finding, airbags and seatbelt pretensioners may not trigger in an emergency. Please have it checked promptly.

The warning light is the direct feedback from the system. It shows the fault even if the car otherwise drives normally.

Which vehicles is the 77960-TAA-J513-M4 fitted in?

The assignment applies to Honda. The airbag control unit 77960-TAA-J513-M4 is fitted in these vehicles: Honda Stepwgn 5th generation (2015-2022).

Take the models from this overview:

• Honda Stepwgn 5th generation (2015-2022)

Compare the part number on the label of your removed unit with this page; this only confirms that it is the right unit. Have the fault memory read out before removing anything. Only this result shows whether the control unit itself is defective or whether a plug or cable is the cause.

How does the repair of the 77960-TAA-J513-M4 work?

First have the fault memory read out and attach the log. Then disconnect the battery, remove the control unit 77960-TAA-J513-M4 and create the repair order online. Processing at Airbag24 usually takes 3–4 working days.

Afterwards, pack the unit well and send it in. The battery must be disconnected before removal, because the control unit is connected to airbags and seatbelt pretensioners.

Airbag24 checks the unit on the test bench, replaces defective components and deletes stored crash data. A function test follows, and then 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-TAA-J513-M4 get to Airbag24?

You send the control unit 77960-TAA-J513-M4 as a parcel, or book a UPS collection for an extra charge. After the repair, Airbag24 sends it back to you by UPS.

Print the repair order you created online and put it in the parcel. Pack the unit so that it resists impact.