if you find that you can crank the engine at the relay, but no power to the key , it may be a couple of things like a bad relay or NSS switch at the transmission. if the car is a 74 or newer, the seatbelt interlock has a reset button on it. to find out if its something besides the relay, you can simply ground the relay to the body and bypass all of it, just remember, the starter will engage in any gear. take a jumper wire off the "G" on the relay and ground it directly to the body. if yours doesnt have a provision for a ground wire, then the relay case to the body is the ground.