If you have lighting or other 12volt appliance like water pump that works ok then check for blown fuse in the lighting circuit.
12volt circuit.....Look for in-line cartridge fuse or the coloured spade fuse on the fuseboard. Both types used in cars. Also check all light bulbs are making good contact , and have good earth [negative side of the battery] don't confuse the mains earth which is green and yellow. You're only interested in the 12volt circuit. You'd be suprised some people get confused about this and think the green and yellow is also earth for the 12volt system.
BB, December 2009
