Surface Pro 3 won't power on

[slees3215]

I've had this SP3 from new. It started to let me down 6 months ago. So I put it on the shelf and bought a 2nd hand SP7. Now that's letting me down too.

The problem with my SP3 is when you press the Start button, it will not start. Nothing happens.

I can't remember exactly what happened back when the problem began. I have 3x SP power adapters and with all 3 the light comes on when plugged in.

I've tried all the combinations of keys when starting. Still nothing happens.

I hadn't used it for 6 months. Then yesterday after I was having problems with my replacement SP7, I thought I'd try it again. And it started first time. I restarted it and it was still working fine. But then today when I tried to start it, back to nothing. I did not think to check the battery level yesterday. But it all seemed to be back to normal.

Maybe it's a failed battery. But whey would it start yesterday after 6 months on the shelf?

Other than that I can only assume it's a motherboard or memory issue. Either way it seems like not worth trying to repair now?.

[#2 · Accepted solution]

The next day I decided to try pressing the power button again and it started again first time.
I noted this time the battery was still half charged. So a flat battery wasn't the reason it wouldn't turn on yesterday.
This time I was able to get the 6 months worth of Win 10 updates done.
I have continued to shut down and restart throughout the day. And it is now working every time.
It's as if it has completely cured itself...something I have not experienced with tech before.
I had previously given up on this laptop because it would not start.

I am no wiser about the cause. So will just wait until it happens again.
It seems like it could have been either, the button itself, software somehow, or the motherboard.