Chosen Solution
It’s just super mushy and doesn’t function as button anymore. To turn it on I have to use the small reset button next to it and I don’t think that’s very good for the computer. I’ve dropped the computer a couple of times, but the button just stopped working one day. Can this be fixed?
Here are a few guides and teardowns that may help you along with a few places to find the replacement part. http://www.myfixguide.com/manual/lenovo-… https://www.youtube.com/watch?v=KDr9BkeD… https://www.amazon.com/90004973-Lenovo-I… https://www.ebay.com/sch/i.html?_from=R4…
I have exactly same problem on my yoga 3 pro after getting it back from service for a faulty sdd. The power button does nothing, but has the white led light. As you I go on using it by pressing the recover/boot options button. I do not think this harms the computer in any way, so I just go on living with this problem. I dissasembled the PC to have a look at the connection of the button to the motherboard, but that dit not solve it. (As a curiosity; the Type and Serial number from BIOS also disappeared after service.)