This also works for the Roland XP-10/30/50/60.
I got a free XP-80 2 days ago, it would turn on but that was it, so i read that there was a possibility that a battery replacement could help, so i did just that.

And unfortunately it didn't help, but in my opinion atleast a good tutorial is now on YouTube on how to do it:

Check the power supply on the XP80.

Did that, didn't see any leaking or other things that could go wrong with capacitors. It did make a buzzing noise when i turn it on. But to be fair i'm not gonna spend more time on it since i've got it for free, i might be able to sell it for parts.

Already sold the 3 expansion boards that were inside LOL.