Airbag control unit with part number 77960-TMB-H140-M4

What does the airbag control unit 77960-TMB-H140-M4 do?

In the vehicle from Honda, the airbag control unit 77960-TMB-H140-M4 coordinates the airbags and seatbelt pretensioners of the restraint system. On the basis of the crash sensors, it decides in a crash, within fractions of a second, which components are triggered.

During normal operation, it checks all connected components continuously. If it finds a fault, it stores it in the fault memory and shows it via the airbag warning light.

After a crash, the unit stores crash data and locks itself. The sensors whose signals it evaluates are connected to the control unit by cables.

Why does the control unit 77960-TMB-H140-M4 fail?

Stored crash data from an earlier accident is the most common cause, even if no airbag has deployed, and a normal diagnostic tool cannot erase it. Aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage peaks are also possible.

Crash data in the memory does not automatically mean that the unit itself has been damaged. Only the check shows whether a component is actually defective.

The other causes are not always visible. That is why reading out the fault memory is the reliable way to narrow down the cause.

How can you tell that the 77960-TMB-H140-M4 is defective?

A defect shows up on the airbag warning light in the instrument cluster, which lights up permanently or intermittently. Typical signs are also an error message, a diagnostic tool that gets no connection, and a fault memory that cannot be cleared.

• The airbag warning light lights up permanently or intermittently
• An error message appears in the instrument cluster
• The diagnostic tool gets no connection to the control unit
• The fault memory cannot be cleared

In an emergency, airbags and seatbelt pretensioners may fail to trigger in the event of such a fault. Have the fault memory read out promptly as soon as the light comes on.

Which vehicles is the 77960-TMB-H140-M4 fitted in?

The airbag control unit 77960-TMB-H140-M4 is fitted in these vehicles: Honda CR-V 5 (2018-2023).

You will find the known vehicles for this part number in the overview below.

• Honda CR-V 5 (2018-2023)

Comparing the part number on the label of the removed unit with this page ensures that it is the right unit. It does not, however, explain the cause. Only the fault memory read out shows whether the control unit itself is defective or whether a plug or cable is causing the problem.

For the same vehicles, we also repair control units with the part numbers 77960-TLA-A240-M4, 77960-TLA-A250-M4, 77960-TLA-A310-M4, 77960-TLA-A320-M4, 77960-TLA-A410-M4, 77960-TLA-A420-M4.

How does the repair of the 77960-TMB-H140-M4 work?

Have the fault memory read out and enclose the log. Then disconnect the battery, and only then remove the unit. Next, create the repair order online and pack the unit well before sending it in.

Airbag24 checks the unit on the test bench, renews defective components, erases stored crash data and performs a function test. Afterwards the unit goes back to you.

Processing at Airbag24 usually takes 3–4 working days, counted only for the testing, repair and function test in-house. 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-TMB-H140-M4 get to Airbag24?

You send the control unit 77960-TMB-H140-M4 to Airbag24 either as a parcel or with a UPS collection booked for an extra charge. After the repair, Airbag24 returns the unit by UPS.

The printed repair order goes into the parcel. The unit must be packed shock-proof.