Sony HT-CT 60 Soundbar - (safety lock)

Hi,

I would like to start repairing my Sony soundbar that broke down two years ago.
I'm sure it's nothing serious and I think someone with a basic understanding of electronics could guide me.

It's very simple: one morning I noticed that I could no longer power on the soundbar.
It only turns on with its remote control, and when it does, there is an LED that indicates the
soundbar is powered on, but since the failure, this LED only lights up for a second and then goes out immediately.

I tried asking some repair technicians I came across, but it's hard to make a diagnosis
without the proper equipment, and given what it must be worth today, taking it to a technician would cost me way too much.

If I understood correctly from what I’m told, it goes into protection mode, probably because a component is no longer working, but which one?

I haven't disassembled it yet, but I can do that on request if more details are needed; I could also possibly post a video of the observed symptom.

Thanks in advance for your help.

The soundbar on the Sony site (the reset in the troubleshooting section doesn't yield any results, obviously)

https://www.sony.fr/electronics/support/home-theater-sound-bars-home-theater-systems/ht-ct60#downloads

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