unless you're under warranty or your rathe rnice in a good sort of way you're likely SOL. I guess they took notice when I got annoyed and bought a refurbished one for $24 maybe $30 in the end and just to be a pain added a $10 warranty to it. Suddenly they were like oh. um oh just send it it we'll fix it for free. Although I have been pushing them on why it happened. Which they probably won't tell me 
they have to take it apart. I've come up with a small theory. How many here are using their Selphy with a battery? One problem with THERMAL dye subs is heat. Which my old Olympus P-10 got too hot it started to stick and jam. I never even thought to block the fan. Which occured to me during all this .. that is exactly what that battery does. It blocks the fan. No fan your frying the components. I threw this on Canon and didn't get an answer on it. I used to build notebooks and with a laptop have a couple of vents to keep it cool (the latest is one that attaches to the outbound fan and is basically a vacuum. Now that cools off my laptop better than one under it ever could.
So logic has always been that Electronics that get hot don't last long. Even LCD tv's with CRT backlit screens (LED's run much cooler)
I'm thinking I should use that battery less or not at all, which is a pain because I'd have to put the wire under the unit because the power comes from the right and the input is on the left in the back. Basically if it is causing overheating because the fan is blocked there should be a wire assem\bly that snaps in place in the back that you can plug into the battery. Like a ribbon cable. Wouldn't be as sweet but it would work. Or a new battery remade that has a ribbon cable out of it that plugs in the back Could be a battery redesign that turns it into a table on the bottom? Just thoughts outloud. But thats what I think it could be but they won't say yes or no if it is.