Airbag control unit with part number 77960-TM8-N810-M2

What does the airbag control unit 77960-TM8-N810-M2 do?

The airbag control unit 77960-TM8-N810-M2 controls the restraint system (SRS) of Honda. It evaluates the signals from the crash sensors and decides in an emergency within milliseconds which airbags and seatbelt pretensioners to trigger. After an accident it stores crash data and locks itself.

The unit monitors the entire system continuously, that is the sensors, the seatbelt pretensioners and the airbag firing circuits. If it detects a fault, it creates an entry in the fault memory and shows the problem via the airbag warning light in the instrument cluster.

The crash data remain stored in the unit even if the vehicle continues to be used after the accident.

Why does the control unit 77960-TM8-N810-M2 fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed; a normal diagnostic tool cannot erase it. Other causes are ageing electronic components, cold solder joints, moisture and corrosion at plug connectors, and voltage spikes, for example from a weak battery or jump-starting.

Crash data are created in the control unit itself and remain stored there, even if no airbag was triggered in the accident. A normal diagnostic tool cannot empty this memory, so the fault persists.

Other causes come into consideration as well:

• electronic components ageing in the unit
• cold solder joints on the circuit board
• moisture and corrosion at plug connectors
• voltage spikes, for example from a weak battery or jump-starting

How can you tell that the 77960-TM8-N810-M2 is defective?

A defect shows itself through an airbag warning light that stays on permanently or intermittently, through an error message in the instrument cluster, through the diagnostic tool being unable to connect to the control unit, or through a fault memory that cannot be cleared. The airbags and seatbelt pretensioners may then fail to deploy in an emergency.

Pay particular attention to these signs:

• The airbag warning light in the instrument cluster stays on or keeps switching on.
• An error message about the airbag system appears in the instrument cluster.
• The diagnostic tool receives no connection to the control unit.
• The fault memory cannot be cleared.

The warning light therefore gives a clear indication of a finding. Have it clarified without delay.

Which vehicles is the 77960-TM8-N810-M2 fitted in?

The 77960-TM8-N810-M2 is fitted in these vehicles: Honda Insight 2nd generation (2009-2014).

Here you will find the models for which this part number is recorded.

• Honda Insight 2nd generation (2009-2014)

Compare the part number on the label of the removed unit with this page. That only ensures you have the right unit in front of you. Whether the control unit itself is defective or a plug or cable is the cause is shown only by the fault memory, which you should have read out before removal.

For the same vehicles, we also repair control units with the part numbers 77960-TM8-A01, 77960-TM8-A020-M2, 77960-TM8-A03.

How does the repair of the 77960-TM8-N810-M2 work?

First have the fault memory read out and attach the log, then disconnect the battery and only then remove the control unit 77960-TM8-N810-M2. Then create a repair order online and send the well-packed unit in. Airbag24 checks it on the test bench, repairs defective components, erases stored crash data and carries out a function test before the unit goes back to you.

This order is mandatory for safety reasons, so the removal always takes place only after the battery has been disconnected.

Processing at Airbag24 usually takes 3–4 working days. This refers to checking, repairing and testing in our own facility.

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-TM8-N810-M2 get to Airbag24?

You send the unit in as a parcel or book a UPS collection for an extra charge. After the repair Airbag24 sends your own unit back by UPS.

Place the printed repair order in the parcel and pack the control unit shock-resistant.