Airbag control unit with part number 77960-TMJ-P110-M4

What does the airbag control unit 77960-TMJ-P110-M4 do?

In the Honda, the airbag control unit 77960-TMJ-P110-M4 takes on the role of the central control unit in the SRS restraint system. It evaluates the crash sensors, decides in an accident within milliseconds on the deployment of airbags and seatbelt pretensioners, and keeps the system under continuous control. After an accident it stores crash data and locks itself.

Monitoring takes place throughout all driving. Wiring, power supply and ignition circuits are checked, and faults end up in the fault memory. They are displayed via the airbag warning light in the instrument cluster.

The lock after an accident does not show while driving. It only becomes visible when a diagnostic tool gets no access to the control unit.

Why does the control unit 77960-TMJ-P110-M4 fail?

Crash data that remains in the memory after an accident is most often the cause, even if no airbag has deployed; it cannot be deleted with a normal diagnostic tool. Other causes are aged electronic components, cold solder joints, moisture and corrosion at plug connections, and voltage spikes.

Stored crash data arises because the unit itself records the accident. Whether a seatbelt pretensioner or an airbag was actually triggered makes no difference to the storage.

The other causes tend to act slowly. Solder joints can lose their contact, moisture and corrosion attack plug connections, and voltage spikes, for example when starting with outside help, strain the electronics.

How can you tell that the 77960-TMJ-P110-M4 is defective?

A defect shows itself through the airbag warning light in the instrument cluster, which burns permanently or intermittently, through a fault message in the instrument cluster, through a missing connection to the diagnostic tool, or through a fault memory that cannot be cleared.

The airbag warning light in the instrument cluster shows the condition most clearly. When it stays on permanently or lights up from time to time, that is a clear sign of a fault in the restraint system.

Airbags and seatbelt pretensioners may in an emergency not deploy as long as the fault persists. Therefore have the system checked promptly.

Which vehicles is the 77960-TMJ-P110-M4 fitted in?

The control unit 77960-TMJ-P110-M4 is fitted in these vehicles: Honda CR-V 5 (2018-2023). The details apply to this part number and to no other.

The vehicles on record are:

• Honda CR-V 5 (2018-2023)

Before you remove the unit, compare the part number on the label with this page. This only confirms that it is the right unit. Also have the fault memory read out beforehand, because only the log shows whether the control unit is defective or whether a plug or a cable is the cause.

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-TMJ-P110-M4 work?

At the start comes the reading out of the fault memory, and the log accompanies the unit; only then do you disconnect the battery and remove the control unit. Afterwards you create the repair order online and pack the unit well. At Airbag24 the processing usually takes 3–4 working days.

Keep to this order, because it serves safety every time work is done on the control unit.

At Airbag24 the unit is checked on the test bench, defective components are replaced, stored crash data is deleted and a function test is carried out. Afterwards 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-TMJ-P110-M4 get to Airbag24?

You send the unit in as a parcel, or book a UPS collection for an extra charge. The return after the repair is handled by Airbag24 via UPS.

The printed repair order belongs in the parcel. Pack the unit shockproof.