Then it has a fault with the power supply - use a known-good wall socket - check the fuse - other than this there's not much you can do without looking inside.
If you have the experience and confidence to poke around inside the equipment you might discover the cause but the chances are that you'll not discover anything.
Weigh in your mind the hourly cost of a repair technician versus the cost of a new one.
Does it have any warranty left on it?, February 2015
