Hi gnweb, did you get your problem figured out? I had this problem a long time ago and it turned out to be the fusible link down by the alternator was blown. I replaced it and everything worked great. Now I am having the same problem again and the fusible link is fine. The switch appears to be ok. Tomorrow I will try cleaning the relay contacts with emory cloth and checking all the system grounds. Did you find the replacement part number for the relay?