Pre-Owned Sansa Clip+ Only Turns On When Connected to Pc

Late reply, but did you see this post a few topics down from yours?

https://forums.sandisk.com/t5/Sansa-Clip-Sansa-Clip/Brand-new-Clip-not-charging-anything-else-to-try/td-p/372257

That’s me.  Same situation.

You have a dead battery and the only solution is to open up the Clip+ and replace it.  There are tutorials and videos on how to do it; it helps to search and read/view all of them to get the Big Picture on how it all works. 

Or you can order a new battery off eBay (there’s one for 17 bucks that’s supposedly OEM for the Clip+)  and try your friendly local PC/phone repair shop to see if they’ll solder it in for you.

Or you can sell it and buy a working Clip+, which is what I did.