laptop ux303l not powering up

Brian,

I hate to say it but I believe your system might be dead.

For arguments sake lets check a couple things.

Check that the light on the charging unit is one (if it comes with said LED light)

Test the power adapter with a multi meter, or another adapter if you have one. (There should be a host of how to's to do this online if not on ifixit.com)

Your RAM could be 'mostly bad'

Your CPU could be 'almost dead'

You could attempt to replace either of the above with a compatible chip if you feel yourself capable or call your local trusted technician to see if they have the parts to test it for you. (most should, but the CPU are more rare if its an older machine).

I would also check the internal adapter and see if it seems loose. It could still be the internal plug if its not loose but this involves a tear down for a $20ish (approx) part.