2000 Won't crank

[2strokecoldsmoke]

Hi, new to this forum, recently bought a 2006 F250 and a 2000 F250 for my business. Love the 2006, that gets the most use, it pulls a heavy gooseneck equipment trailer most of the time.

The 2000 had some electrical issues under the dash when I bought it. Now it suddenly won't turn over when the key is turned. Everything comes on when the key is turned to the RUN position, turn the key to the START position, most everything shuts off like it should, but nothing happens.

The pre-existing electrical problems was that the instrument cluster and the accelerator pedal would intermittently lose power. Knocking or pressing the back of the fuse box under the dash fixes it. So I know there is something wrong in that area, still tracking it down.
The windshield did leak when purchased (a common problem I am told), that has been fixed with a new windshield.

Any insight on why the starter won't engage would be appreciated. I hate taking a truck with an electrical problem to a mechanic, that can get really expensive really quick.

[JSchuricht]

Start from the alternator and work back. With a multimeter or test light, check for 12v on the large wire, then check the small wire while someone turns the key to start. Then check the relay on the passenger side fender under the hood. There are several wires a large one coming in that should have 12v, a wire going out to the starter and one going to the ignition switch. Check that you have a constant 12v then check the other wires while someone turns the key to start. Next I would move to the ignition switch but I don't know the wire color.

[2strokecoldsmoke]

Thanks, I'll do what you suggested tomorrow, dark outside now, and report back.

[Turbostang500]

I would first try pulling the truck into neutral and seeing if it will crank.
the neutral safety switch might be messing up.