If the disconnect relay is malfunctioning, you can easily test it by using a jumper cable to bypass it. It normally would have a large wire coming to it, and a large wire going away from it. Put the jumper from one large wire to the other large wire. It would also have two small wires that go to the disconnect switch. Many have a fuse on them as well that can be checked. If you have full voltage going into the relay, but not full voltage coming out, the relay is defective. If it is defective, a temporary solution is to just put both large wires on one of the terminals. This will bypass the relay, so the switch wont work, but many people don't care about the switch, and permanently bypass the relay.
