Should be rather easly resolved.. The relay is either excited by a + or a - signal.. By checking out the switch one should be able to find which.. I'd bet on a - signal and the wire has rubbed somewhere. giving a signal at all times.. Maybe not.
Or the relay itself could be going south. To find out simply switch relays with onother one..
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

professional bovine relocation specialist