Almost certainly a FUSE has blown. Find the fuse box (generally by the driver's knees inside the car), there will be loads of fuses in there ... don't start yanking them out wholesale, be calm and methodical!
There will be a grid / chart inside the fuse box that tells you which fuse does what ... track down the one you want and pull it out. I bet you'll find it blown. Make sure that it is the right size fuse. For example if you have a 5 amp fuse where you should have a 10 amp one ... of course it's going to blow!
Simply replacing the fuse with a good one of the right number of amps will probably solve the problem but keep in mind that there might be a problem that is CAUSING the fuse to blow, so if it goes again then the problem may be a bit more complicated.
Mike Rochester, May 2010
