Airbag control unit with part number 77960-TLA-Z640-M4

What does the airbag control unit 77960-TLA-Z640-M4 do?

The airbag control unit 77960-TLA-Z640-M4 is the control unit of the restraint system (SRS) for Honda. It evaluates the crash sensors and decides in an accident within milliseconds whether to trigger the airbags and seatbelt pretensioners, and reports faults via the airbag warning light. After an accident it stores crash data and locks itself.

The control unit monitors the system throughout driving operation. All deviations found are recorded in the fault memory, which a diagnostic tool can read out.

The lock is only lifted by the repair at Airbag24.

Why does the control unit 77960-TLA-Z640-M4 fail?

The most common cause is crash data stored after an accident, even if no airbag has deployed. The further causes are summarised below:

Crash data cannot be erased with a normal diagnostic tool. Airbag24 erases it during the repair.

• aged electronic components
• cold solder joints
• humidity and corrosion at plug connectors
• voltage spikes, for example from a weak battery or jump-starting

How can you tell that the 77960-TLA-Z640-M4 is defective?

The airbag warning light in the instrument cluster lights up on the 77960-TLA-Z640-M4 permanently or intermittently, and the instrument cluster shows a fault message. The diagnostic tool gets no connection to the control unit, and the fault memory cannot be cleared.

In an emergency, airbags and seatbelt pretensioners may then not deploy. The signs in detail:

• warning light that stays on permanently or intermittently
• fault message in the instrument cluster
• no connection to the diagnostic tool
• fault memory that cannot be cleared

Which vehicles is the 77960-TLA-Z640-M4 fitted in?

The 77960-TLA-Z640-M4 is fitted in these vehicles: Honda CR-V 5 (2018-2023).

The following overview lists the vehicles for which this part number is on record.

• Honda CR-V 5 (2018-2023)

Compare the part number on the label of the removed unit with this page. This only ensures that it is the right unit. Have the fault memory read out beforehand, because only this log shows whether the control unit or a plug or cable is the cause.

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-Z640-M4 work?

First, have the fault memory read out and enclose the log. Then disconnect the battery and only after that remove the control unit. Next, create a repair order online and send the unit in well packed.

Airbag24 checks the unit on the test bench, repairs defective components, erases the stored crash data and carries out a function test. Processing usually takes 3–4 working days, after which the unit goes back 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-Z640-M4 get to Airbag24?

You send the control unit 77960-TLA-Z640-M4 in 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.