akbashboy

Restoring a 1987 F-150 5 liter, having issues with the key. When I turn the key nothing happens, but when I make a direct link from the battery to the starter the truck will turn over. Followed the wiring from the key through the dash to the four unplugged wires in the picture. Cant seem to figure out where these plug into, I think there is a part missing where the wires are, any thoughts on where the wires could go or what piece is missing?

Varner351

That plug is used to check engine codes on the computer with code reader. What you also show in the picture is the fuel pump relay and ECC power relay. One of the relays is missing the top which isn't good as it can touch metal and short. If the ECC power relay goes the truck won't run. I don't remember if it will crank over still or not. I had the ECC relay go bad off roading years ago on a truck and used a piece of wire with blade crimp on terimals to jump the relay socket. It stayed like that for a couple years till I junked the truck because the parts store wanted $80 something for a new relay.

Varner351

My bad its the EEC power relay

Varner351

If you spend a lot of time in mud or water holes. Them relays like to go bad a lot as they get wet. I know I replaced around 6 fuel pump relays in about a year and jumped the EEC power relay.
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akbashboy

Do you know which is the EEC power relay and the fuel pump relay?

Varner351

I believe the green relay missing the top is the fuel pump and the brown relay is the EEC.
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icu1954

if the relay is not bad,may be the ecm.

Varner351

I whould check the wire that's kicks in the starter relay for power. It should have power to that wire when the key is in the cranking position. If it has power then your starter relay is bad. If it doesn't have power then i would check all fuses, if they're good I would replace the ignition switch under the steering column.

Varner351

Varner351

The "start switch in" wire, is the wire that should have power when key is in cranking position.