chances are it will have a feed straight from teh fuse board and be labled up.
have a check and if it is and you turn it off you should be ok to open it up and have a look.
would advise you check it with some voltage testers first though.

it might just be loose and need tightening up, or burnt out.
either one you capable of fixing really and saving some money.

but i never told ya to do it