No boot, all leds on except battery and HDD

Hello,

I tried to give as many details as possible to what I did and how the issue came to be.

The story:

I own an Asus R510L laptop. It was resting for a good time without use as it has a keyboard button issue where it was always pressed.

Instead of having it as a nice e-trash, except the keyboard it was a very good laptop for watching movies on a travel. So I got it out of the box and tried to start it.

Absolutely nothing happened when I press the button, no led, no screen, nothing. After a long time in the forums, I had to completely disassemble it and do a bios reset by removing the battery, checked the battery and it was still at 3V which is good.

After the hard reset, the computer came back to life, I was welcomed by the BIOS screen and I was very happy.

So, I turned it off, reassembled everything with the HDD, and I booted it up.

My windows locking screen on the sight, I didn’t go though as the keyboard issue was still there, but I told myself I’ll solve it later. So, I grabbed an SSD I wasn’t using much, I put it in the PC, and from that moment it refuses to go on.

I tried to remove the SSD and try to boot without any drive and the computer stayed off and I noticed that all the leds were on except the battery and the HDD. And there, I tried everything, hard reset, start with only DC, only with battery, reseat the ram and absolutely nothing changed.

The behavior is the following:

On battery: Computer off, when I press the ON/OFF button, leds mentioned above go on and nothing happens. If I long press the ON/OFF button the computer force shutdown successfully and the leds go off.

On DC: Leds goes on as soon as I plug the DC jack, still nothing else happens, no battery charge indicator even with the battery on, when I try to force shut down with the ON/OFF button, the leds goes off for a split second then goes on again.

I have no idea what to do to diagnose the issue, can you help me please ?