wiring issue

[BuzzGun79]

stll having troubles with the charging system on the 79 f 250 60 amp alternator, it is runing off the battery, volt meter shows 12.3 volts when runing in the truck {aftermarket guage} & at battery {hand held meter}. dash cluster light is non functional due to the harness being hacked and the plug cut off in which i did not do.basically using it as a speedometer.alternator is the 3rd {fresh unit just installed} one & regulator is new.i have 12.3 volts power going to the alternator,but no out put from the field or stator wires on the rear of the alternator to regulator when runing.since it did work previously i know these wires are not crossed.i do have key on power to regulator,new ignition switch as well,im assuming a wire has broken,or ground loss.ive tried jiggling all the wires while runing but nothing.not sure where to start tracing & im no electrician by any means.any help would be appreciated thank you...Bob

 

[Evan's f250]

Make sure there is a small brown wire connected to the side labeled "I" on the starter solenoid. This is the low voltage ign wire that triggers the charging system to charge. My truck wasn't charging and this was the problem, I had a new alt and regulator as well. Since these trucks charge through the solenoid, this wire is needed to charge.

 

[Evan's f250]

this small brown wire labeled "I" comes out of the regulator, it will also be labeled "I" or "IGN" on the regulator wire plug.

 

[Evan's f250]

I got your msg that this wasn't the problem. Have u tried seeing if the main alt. power wire was getting pwr all the way across?(use test light)

and if you haven't already, use that the other small wires going to the alt. are getting juice @ the correct times.(use a test light for this as well)

Has your truck never charged or is it just been recently?

 

[BuzzGun79]

when i first drove the truck it would show up as 12.3 volts,i would wiggle the ignition key then it would jump to 13.5 ish.it ran like this for a while.parked it one day, it sat about a week,started it up 12.3 volts is all i can get out of it now.though it might be in the ign,switch so i put a new one in,but this did not fix it.power is getting to the battery terminal of the alternator,i get nothing from the field or stator wires.this is the 3rd alternator & still the same issue,this alternator was tested when it was rebuilt and has a passed notification tag on it. Napa unit,the duralast unit i returned also passed bench testing.it just doesnt make sense to me at this point in time,i also have key on power at the regulator.

 

[Alvin in AZ]

when i first drove the truck it would show up as 12.3 volts,i would wiggle the
ignition key then it would jump to 13.5 ish. it ran like this for a while. parked
it one day, it sat about a week,started it up 12.3 volts is all i can get out of
it now.though it might be in the ign,switch so i put a new one in,but this did
not fix it.

power is getting to the battery terminal of the alternator,i get nothing from
the field or stator wires.this is the 3rd alternator & still the same issue,this
alternator was tested when it was rebuilt and has a passed notification tag
on it. Napa unit,the duralast unit i returned also passed bench testing.it just
doesnt make sense to me at this point in time,i also have key on power at
the regulator.

Autozone has wiring diagrams. You might have to sign up first to see them
tho? Anyway, type in- wiring diagram -in the parts search window.

So far you've got voltages and that tells me you have a voltmeter.

But you're going at it like you don't have a voltmeter, you're going at it using
the "gambling-method of electrical troubleshooting and repair". Let the meter
tell you -exactly- what the trouble is and stop guessing at it. It will lead you
to the trouble every-time, if you let it do its job. No kidding.

--------------------------

I'm not an electrician either, Buzz!

One time a signalman in the System Signal Shop said "if we get laid off we
can be electricians " Oops. "Richard Smith, there's more to someone's job
than understanding electricity" -Alvin

He disagreed.

"oh yeah? well then what color wire goes to the larger slot in the wall outlet
then? " "trick question! LOL ...they are both the same size! LOL " -R.S.

We had to walk around the shop to prove it, he wouldn't believe the -real-
electrician sitting next to me rebuilding relays... Roman Gardia.

Alvin in AZ knows about halfassed about automotive wiring, but we can fix
this thing and stop wasting money both at the same time, if you're game!

Found this for sale on the internet...
http://www.panix.com/~alvinj/file12/dn11.jpg
RMG in script = Roman Gardia

 

[Evan's f250]

Checked mine..."F" wire that goes from regulator to the alt. is supposed to be hot with the key on. The "F" wire should be light redish in color. My "F" wire read 7 volts on the meter at the alt. with the key in the on position.

 

[Mil1ion]

Ignition switch Pin out

 

[Mil1ion]

are you checking for charging.... at idle or at 1200 RPM + ?

 

[BuzzGun79]

After a day of tracing & testing circuts & banging my head against the wall...i am glad to report i found the trouble.the prolblem lied in the cluster plug.there is a green & red stripied wire coming off the regulator & i followed it to the cluster wiring,since the wires were cut off at the plug,i had to find its power source being a black & yellow striped ignition wire from the diagram above.once i hooked up these to leads,the truck began to charge,my volt meter in the truck is reading close to 14 volts at 1200 rpm,it does drop a little at idle between 13- 13.5 ish,upon accelleration it goes back up.ide say we can now put this issue & thread to rest finally.THANK YOU TO ALL FOR YOUR INPUT & DIAGRAMS!!! i will print these off for future reference...now i can button her up & maybe get a couple LONG cruises in before the snow flies!!!...Bob

 

[Alvin in AZ]

Snip

Cool wiring diagrams, Dennis.

BTW, it was you that I'd read that said Autozone having wiring diagrams.

Alvin in AZ

 

[Mil1ion]

The ones above are from OLD reference books and online sources

I am having trouble finding my copy of a Ign switch pin-out test so if you find one please let me know

 

[Evan's f250]

glad ya got it going, glad your conversation about it on phone was atleast a little helpful..