No electrical power
 

I have a 1989 F150 with a 5.0 engine. I have no electrical power to anything. No headlights, no gauges, windows don't work, radio doesn't work, truck won't start.....I hope you get the picture. ;) It's exactly like the battery isn't hooked up.

The battery tests out just fine. Took it to two different places to be sure. Removed starter and it tested bad so I replace it and the starter solenoid (on passenger side fender). Pos and Neg battery cables have been replaced and still nothing. I can't even jump the starter at the solenoid with a screwdriver. One time when this first happened I attempted to jump start the truck. Lights came on, windows worked, gauges, etc but it wouldn't turnover. Just one click and that was all (that's when I tested the starter). Since then a jump start won't even cause anything to happen.

Any ideas on what could possibly be wrong that would cause this type of condition?

(Just a shot in the dark.) You might pop the hood and check the big plug as the wiring harness passes through the firewall. I've seen one come a little bit loose and knock out all of the power on an "85" F-250 before.

I checked the wire harness that connects to the firewall and it's fine.

Does anyone know where each of the smaller wires on starter relay are supposed to go? I have the one from the battery to the relay on the correct post and the large black cable from the other post to the starter correct. The small push on wire is on the top small terminal connection. I've finally been able to "jump" between the post with the battery connection to the small top post and get the engine to crank but no start.

What's left are 4 smaller wires, 3 are yellow and 1 is green. Through tinkering with it, right now 2 of the larger (18 ga. I believe) yellow wires are on the battery side post and the other yellow and green wires on the other side. The truck now starts and everything works but I'm just not sure if that's correct or not. The battery light is now on and the amp gauge is sitting on the low side. The battery and the altenator have been replaced.

If anyone has a picture of where each wire goes and can tell me, it would be greatly appreciated.

Thanks.

My 1989 F150 has no electrical power I have checked battery, battery cables, solenoid but nothing