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Hi,I have one question, On my 2003 F250 Superduty I'm having charging issues. The previous owner had put a new alternator and I've put 2 new batteries. Yet after running a bit batteries goes dead and can't start the truck anymore.
I noticed the truck had only one wire going to the alternator but the alternator also have a 3 pin connector on it.
My question is: Are one wire alternator the same as OEM alternator? I'm suspecting the previous owner replaced the alternator with and OEM equivalent without knowing the truck was converted to a one wire. Can this be the source of my issue?
It would be good to know what your voltage is when the truck is running.
The 6G alternators use the outer 2 of 3 pins in our trucks, turn-on, and sense (to know the voltage). However, there are conversion kits to go to a 3G alternator and a "one wire" setup. As GM does, the one-wire setup loops the "sense" function with a small external loop or internally to the output post.
Again, to know if it's functioning, you would have to tell what voltage you are getting.
Without much detail to go on, people who have working alternators but come out in the morning to find their batteries severely diminished without cause should check how warm the glow plug controller is on the front of the passenger valve cover when they fail to permanently on, the glow plugs being constantly engaged to prevent the batteries from being fully charged and drain down the batteries in a few hours.
You have one big wire (B+) >> Alternator bolt M6, nut 10mm
You have one 3pin connector, but only 2 wires in there.
Please make a pic of your situation.
THis is the st-up I have from a wire stand point but the previous owner (My Dad) installed a regular alternator. Unfortunately the truck in about 500 miles away so I'll get pictures and voltage check next time I go in about a week
It would be good to know what your voltage is when the truck is running.
Again, to know if it's functioning, you would have to tell what voltage you are getting.
Without much detail to go on, people who have working alternators but come out in the morning to find their batteries severely diminished without cause should check how warm the glow plug controller is on the front of the passenger valve cover when they fail to permanently on, the glow plugs being constantly engaged to prevent the batteries from being fully charged and drain down the batteries in a few hours.
Last time I checked I was getting about volts 11.5 to 12 volts on each battery when the truck was running. I did not test directly from the alternator. I'll test that at my next visit. Hopefully I can find a quick fix and bring the truck back home
Originally Posted by TooManyToys.
It would be good to know what your voltage is when the truck is running.
The 6G alternators use the outer 2 of 3 pins in our trucks, turn-on, and sense (to know the voltage). However, there are conversion kits to go to a 3G alternator and a "one wire" setup. As GM does, the one-wire setup loops the "sense" function with a small external loop or internally to the output post.
So just to confirm a one wire alternator is different from a regular alternator. Meaning since I only have one big wire going to the alternator and no other wire available on the truck for the 3 pin on the alternator it would mean the previous owner installer a regular alternator not knowing the truck already had a one wire wet-up.
What would be the quickest way to get this truck going. Buy and install a one wire alternator? Modify/install something to convert back the truck to a regular alternator?
There can be several issues going on. Voltage measurements at the alternator and at each battery when running would be great, along with pictures of the batteries' tops. We've had issues like this when one of the battery to battery positive terminals is broken, and the cable connecting the two batteries has separated. The passenger battery charges and starts, the driver's battery that connects to the electronics depletes down.
Or maybe, someone forgot to plug in the other wires and the connection is tucked out of sight?
I would rule this out as I just swapped the 6.0 and there was no wires tucked away. I triple checked all connectors as I was swapping the engine.
Also since my dad was the previous owner he confirmed there was not other wires to the alternator when he installed a new one. He just did not know about one wire versus regular.
There can be several issues going on. Voltage measurements at the alternator and at each battery when running would be great, along with pictures of the batteries' tops. We've had issues like this when one of the battery to battery positive terminals is broken, and the cable connecting the two batteries has separated. The passenger battery charges and starts, the driver's battery that connects to the electronics depletes down.
I'll ask someone to do some voltage reading for me and send some pictures. My hands an feet over there should be available by end of week.
THis is the st-up I have from a wire stand point but the previous owner (My Dad) installed a regular alternator. Unfortunately the truck in about 500 miles away so I'll get pictures and voltage check next time I go in about a week
I need to correct my statement. I only have wires going to the 10 mm hex nut and nothing else.
Probably need to find the rest of the alternator harness, its definitely there. Its required or you won't charge, there was no such thing as a one wire alternator from the factory.
There can be several issues going on. Voltage measurements at the alternator and at each battery when running would be great, along with pictures of the batteries' tops. We've had issues like this when one of the battery to battery positive terminals is broken, and the cable connecting the two batteries has separated. The passenger battery charges and starts, the driver's battery that connects to the electronics depletes down.
I had an alternator in a 1988 Ranger with the field stuck in the on state and it was warm and
the battery was almost dead when I had gone to check it. Turned out to be a bad regulator.
Here is the wild part. When running it was putting out 18+ volts.
ok here's picture of the Alternator in the truck. I get 13.5 volts on each Batteries when the truck run and like the previous alternator only have one wire going to it.
But for some reason after a short ride battery get's to low to start the truck up again. This is with 2 brand new batteries.
"One-Wire" does not mean the one cable to the output post, which is screwed up anyway, as the end that is supposed to go to the passenger battery post is connected to the alternator.
That little grey connector at the back right should have a plug in it. If that is truly a "one wire" alternator, which I now have serious doubts, it needs to have the harness plugged into it. Thank God it didn't, because if it did, wherever the cable end is supposed to be on the alternator, it would have been shorting like crazy.
You need to expand your hunt for cables and connectors or get someone familiar with the truck.
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