Airbag control unit with part number 77960-TXM-J330-M4

What does the airbag control unit 77960-TXM-J330-M4 do?

The airbag control unit 77960-TXM-J330-M4 forms the control centre of the SRS restraint system for Honda. It reads the crash sensors and decides in an accident within milliseconds whether airbags and seatbelt pretensioners are triggered. At the same time, it checks the system continuously and reports faults via the airbag warning light.

The unit is active throughout the entire journey. After an accident, it stores crash data and locks itself.

For the evaluation to work reliably, the control unit needs a stable power supply and intact connections to the sensors and triggers.

Why does the control unit 77960-TXM-J330-M4 fail?

For the control unit 77960-TXM-J330-M4, the most common cause is stored crash data after an accident, even if no airbag has deployed. Other causes include aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Crash data cannot be erased with a normal diagnostic tool. A simple attempt to erase it therefore achieves nothing.

Electronic components age, and solder joints can be cold. Moisture and corrosion attack the contacts.

Voltage spikes from the vehicle electrical system occur, for example, with a weak battery or during a jump start, and stress the circuit.

How can you tell that the 77960-TXM-J330-M4 is defective?

The airbag warning light in the instrument cluster indicates a defect in the 77960-TXM-J330-M4 when it lights up permanently or intermittently. Also present are an error message in the instrument cluster, no connection between the diagnostic tool and the control unit, and a fault memory that cannot be cleared. In an emergency, the airbags and seatbelt pretensioners may then fail to deploy.

The warning light is the clearest sign, and the error message confirms it in the instrument cluster.

Only the readout of the fault memory shows whether the fault lies in the control unit itself.

Which vehicles is the 77960-TXM-J330-M4 fitted in?

This control unit is intended for Honda. The 77960-TXM-J330-M4 is fitted in these vehicles: Honda Insight 3rd generation (2018-2022).

We have the following details on record for this part number:

• Honda Insight 3rd generation (2018-2022)

Compare the part number on the label of the removed unit with this page. This only clarifies whether it is the right unit, not whether it is defective. Whether the control unit is defective or a plug or cable is the cause is shown by the fault memory, which you should have read out beforehand.

For the same vehicles, we also repair control units with the part numbers 77960-TXM-A23, 77960TXMA230M2.

How does the repair of the 77960-TXM-J330-M4 work?

First have the fault memory read out and enclose the log, then disconnect the battery and then remove the 77960-TXM-J330-M4; online, you then create a repair order and send in the well-packed unit. Airbag24 checks it on the test bench, repairs defective components, erases stored crash data and carries out a function test before the unit is returned to you. Processing at Airbag24 usually takes 3–4 working days.

The order is mandatory because it serves safety.

The repair order is created online before the unit goes into the parcel.

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-TXM-J330-M4 get to Airbag24?

You send the control unit 77960-TXM-J330-M4 as a parcel or book a UPS collection for an extra charge. After the repair, Airbag24 returns it to you by UPS.

Put the printed repair order into the parcel and pack the unit shockproof.