'86 F-250 Electrical Trouble

[Wbcody]

Okay here's an interesting situation for all you pro's out there. I got an 1986 F-250 Diesel here and when I went to start the truck, I lost all electrical power. The batteries are fully charge and load tested within stanards.

When I got into the truck, the dome light was on and buzzers were ringing away like they should be. But as soon as the ignition key was turned everything went dead and has since remained dead. And the key wasn't even fully turned before it died. In looking under the dash and under the hood, there is no visible signs of anything shorting out. I took a test light to the fuse panel and everything is dead except for one fuse that supplies the emrgency flasher and nothing else. So out of curiousity I pulled the hazzard switch and the lights do blink. But nothing else on the truck works. Everything was working fine three days ago when I pulled it up into the driveway and shut her down.

Now could there be a short in the ignition switch killing 99% of the electrical system without draining the batteries, or is the problem much deeper than that? I don't really want tear the steering column down and pull the switch if that's not the problem. Kinda of lost here.

 

[suv7734]

There's been a few of these lately and the common problem is the battery connections or ground connections that 'look' good but aren't. Pull the connectors off the batteries and clean them and the posts so they're nice and shiny. Check the two main ground connections at the block. Try it again after that.

 

[EB1156]

Check for any fusible links at the battery connections, starter, or starter relay. They may not look bad visually, but may be burned up inside the insulation preventing electricity flow.

 

[Wbcody]

There's been a few of these lately and the common problem is the battery connections or ground connections that 'look' good but aren't. Pull the connectors off the batteries and clean them and the posts so they're nice and shiny. Check the two main ground connections at the block. Try it again after that.

Actually that is one of the 1st things I did when I load tested the batteries. I had pulled the cables so I could check each battery individually and I always scrub the posts clean and check connections when putting things back together. Thanks for the try tho...

 

[Wbcody]

Check for any fusible links at the battery connections, starter, or starter relay. They may not look bad visually, but may be burned up inside the insulation preventing electricity flow.

I don't remember actually seeing any fusable links in there but I will check. I'm not really convinced thats where the problem lies tho as I never even made it to the staring circuit. I mean this thing popped just as I cracked the key. I'm talking like fractions of an inch here as I just started turning the key on.

 

[Wbcody]

Okay guys I found the problem. Thought I would post it up here for anyone else that might experience this.

Under the hood on the passenger side there is a wire harness with a bunch of wires next to the solenoid that engages the glow plugs. There is a couple of fusible links in there and a little white two-wire connector that has a fat lime-green wire on one side of it. That connector is the culprit. It seems to have taken a lot of heat over the years and is pretty much worn out. When jiggling the wires around I can see the hood light flickering on and off. Once I got it set so the hood light would stay on, I went and turned the ignition key, and everything went dead again. This time leaving the key on in the "on" position, I went back and jiggled the wires again and this time I can hear the glow plug solenoid clicking. Once it was all stabilized again, I went back and turned the ignition key the rest of the way and the truck fired up and came to life. This seems to have been a problem in the past as somebody had strung a tie wrap around the connector to snub it up tight.

I want to thank the two guys that did reply back in effort to help. Hopefully this will help out someone else experiencing the same type of problem.