Hey, I'm new to this stuff (the posting part.) My girlfriend's truck has a 3.4A short somewhere between the ignition switch and fuse block (no fused circuits are the culprit.) It started suddenly on the way back from a long trip. I checked horn relay and light switch per the schematic. The draining 12ga yellow wire heads up from the switch into the dash. Anyone have any more clues before I start tearing out the cluster? Someone please amaze me with a quick fix. Oh, and tell me if this is how I'm supposed to do this. Thanx.

 

I dont think this is any quick fix but in my schmatic it shows it feeds the headlamp switch, dome light, emergency flasher and horn relay. Are you having trouble with any of those items? Something stuck or shorted out in those area's maybe?

 

...Welcome Pocca, to Ford Truck Enthusiasts!


…..See you on the boards.

 

Thanks guys. I'm not much of a Ford guy, but it's been a pretty good truck. Being in AZ, you find some pretty pristine stuff, and this thing is pretty sano. A few electrical debaucheries, but other than that the 460 rocks. I'd like to post a picture of my cowboy hood latch fix, but the thing says I can't post attachments. Probably have to insert a quarter or something, heh. Still looking for the zorch...

 

the yellow feeds the dome light,cig lighter and glovebox light and cargo light if you have one

 

Way good info, hogman. It's got a camper on it so I'm unsure about the cargo. If it has one where's the switch? I will faint if it's something inadvertently left on...but I still wouldn't be surprised. She's a great gal, but somewhat of a cadet. Eh, I have my own moments. Big thanks for the leads!!!

 

the switch is on the drivers side middle pillar about head height it says cargo light on it along with off and on. the cargo light does pull about 3.2 to 3.6 amps so maybe that is your problem.

 

Do the finding a short or current drain procedure with a test light & removing the fuses one at a time

Btw, May I suggest putting the topic in the title of the thread ?

It make is easier & faster for people to search the same problem plus, we know what to expect when we go to read the post

 

Sure, you can suggest anything, however you have to give a newbee like me some clue as to how to do it. Can I change a thread title as I go? This thing started as a short and now it's getting to be a long, heh. I are an en-gin-eer. I would have titled the thread, "1978 Ford F-250 2WD 460 Starter relay to Ignition switch ground fault," had I been writing a report, but I figured you blue blob motor hounds would peg me as a real geek. Ooops, I guess I let the feline from the flexible containment vessel. No worries, this stuff is just new to me. It has been a grand help, though. Oh, I did originally say that the short was prior to the fuseblock, just for clarification. Thanks once again, hogman. I'll try to diagnose 2nite with the help of a very remote tall redhead.

 

Eeyeyeyi. It gets deeper. I checked out Dome light, Cig lighter, glove box light (none) and then tore out the dash. Found a couple of future, "Why won't this thing run?" electrical hacks. I then proceeded to the horn relay... The relay looked good, but then I noticed that the hot wire ran to - the dreaded voltage regulator. I had already looked at this which has me confused. The only thing I can figure is that either the fusible link from the alt to the starter relay wasn't blown then, but is now (due to some limp mode use), OR I just missed it. Regardless, if a manual ever says, "if the accessories work this fusible link isn't blown," don't believe them. Some past rocket scientist MAY have just wired around it (thank you past rocket scientist!) I'm going to replace the link, test, and if I control the short, replace the regulator. I'm not sure if a bad regulator will take out a link like that, but??? I think I'm supposed to ask a moderator to move me to a new forum, but I don't know how to ask. That is actually good, as I don't know how to get to another forum. Still so much to figure out. Eh, I'll keep working on the truck. This place seems to be full of librarians... The real dudes have been great, though. Hey, anyone want to buy a Mercury, ha, just kidding. Gonna cruise it up and down the road...

 

pocca just click forums it will bring you to a whole list of different forums you can post in.

 

Got it hogman. Thanks for the clue. Sometimes my light is dimmer that the truck's (with a bad ground, of course.) Oh, I just remebered what does PITA stand for, hoggie?!?