Airbag control unit with part number 77960-TLA-Q040-M4

What does the airbag control unit 77960-TLA-Q040-M4 do?

The 77960-TLA-Q040-M4 is the central control unit of the restraint system (SRS) in Honda vehicles. It evaluates the signals from the crash sensors and, in an accident, decides within milliseconds which airbags and seatbelt pretensioners are triggered. It also monitors the entire system.

If the unit detects a fault, it reports it via the airbag warning light in the instrument cluster.

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

Why does the control unit 77960-TLA-Q040-M4 fail?

The most common cause for the 77960-TLA-Q040-M4 is crash data stored after an accident, even if no airbag has deployed. In addition, ageing components, cold solder joints, moisture and corrosion at plugs and voltage spikes may be the reason.

A normal diagnostic tool cannot erase this data. Airbag24 removes it during the repair.

The other causes are general in nature. Electronic components age, solder joints can be cold, and moisture promotes corrosion at plug connections. Voltage spikes occur, for example, with a weak battery or when starting with a jump start.

How can you tell that the 77960-TLA-Q040-M4 is defective?

On the 77960-TLA-Q040-M4, the airbag warning light in the instrument cluster lights up permanently or intermittently, and the diagnostic tool does not connect to the control unit. A fault message in the instrument cluster and a fault memory that cannot be reset are also present. As long as the fault persists, the airbags and seatbelt pretensioners may not be able to deploy in an emergency.

The warning light makes the defect visible. Take this indication seriously and have the system checked.

A connection error with the diagnostic tool, or a fault memory that cannot be reset, likewise indicates a malfunction.

Which vehicles is the 77960-TLA-Q040-M4 fitted in?

The 77960-TLA-Q040-M4 is fitted in these vehicles: Honda CR-V 5 (2018-2023).

The list shows the vehicles known to us for this unit:

• Honda CR-V 5 (2018-2023)

If the part number on the label of the removed unit matches this page, it is the correct unit. Whether it is defective, however, only the fault memory shows. Have it read out beforehand, because a connector or cable can be the cause just as well.

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-Q040-M4 work?

For the repair of the 77960-TLA-Q040-M4, first have the fault memory read out and enclose the log. Then disconnect the battery before removing the control unit, and send it in with a repair order created online. Airbag24 requires 3–4 working days for inspection, repair and testing.

Airbag24 checks the unit sent in, repairs defective components, erases the stored crash data and carries out a function test. Your own unit is then 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-TLA-Q040-M4 get to Airbag24?

You send the control unit 77960-TLA-Q040-M4 as a parcel, or book a UPS collection for an extra charge. Airbag24 sends it back to you by UPS after the repair.

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