i know this is a really stupid question but are u sure that the wires on the battery are the right way round, if i remember rightly u have two black wires one goes to positive and one to negative, at least i know my old rst did! i only know something about this cos i called an auto electrician out ot my rst cos half of the electrics didnt work, he spotted it straight away that i had one of the wires on the wrong terminal!!!