If your 1997 Ford Expedition won't start and your starter fuse and battery are OK, your starter relay is most likely the problem. This will be confirmed if you can't hear the solenoid click and start to crank the engine over. But you don't need to be a mechanic or any special tools to troubleshoot the starter relay. However, you will need a friend who is not afraid to put his hands under the hood to help you.
Open the hood then open the engine compartment fuse panel located on the driver's side near the windshield. The cover just snaps off, and the relay will be marked.
Instruct your friend to touch the relay as you try to start your Expedition. If it doesn't click, the relay is bad, and you should replace it. If the relay clicks, the coil and wiring do not have any problems, but your relay contacts could still be bad.
Turn the ignition off then pull the starter relay out of its socket. Place a small piece of 14- to 20-gauge wire between pins 30 and 87 of the relay socket. Try to start the engine again but only hit the starter briefly. If the engine starts to crank at this point, the relay is definitely bad, and you should replace it. But do not start the engine with this wire in the relay socket as the starter motor may continue to crank. If the engine still won't crank, your relay is probably OK, and you have another problem.
