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Alternator wiring problems
#1
        I have a 73 mustang but I believe the engine etc is out of a later car (probably around year 85).  I've had a lot of issues with the wiring on lights etc.  I figured I had a bad alternator so I took it to autozone, they tested it and it failed.  
Purchased new and installed today but car still dies when battery post is removed.
I found a few wires that are loose that are on the alternator plug.  One green w/red strip, other is tan w/brown strip.  Can anyone tell me where these go?  

thanks
Bob
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#2
This should help
https://www.7173mustangs.com/thread-alte...#pid320622

You can also download the wiring diagrams for your car under the Mustang Data tab at the upper right of this page.



“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
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#3
OK, I believe I have a 3G system, my wiring plugs look a little different than the diagram. I found the light green wire and re-connected it. When I do the alternator makes a little different sound and a small bulb in dash comes on. My dash cluster is completely out so I'm guessing the bulb is the idiot light for the amps. I can not figure out from the diagram where the white w/black strip wires goes??

thanks
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#4
Do you have a voltage regulator mounted on the fender apron near the starter solenoid? If so, you do not have a 3G alternator. The 3G alternator has a built-in regulator.

Pictures of what you have would help.

If you do have a 3G, the white/black wire loops back to another terminal on the alternator. This should help

[Image: 3g-with-alt-light-original.jpg]



“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
  Reply
#5
I do not have an regulator, it's internal on alternator. I got the pics attached.
The 3 wires on the left plug and the first wire on the right plug all go back to battery side of solenoid.
thanks
  Reply
#6
Don C, I think I've got it figured out thanks to your last post.  The white w/black wire was ran back to the solenoid.  I reconnected it to the other plug on alternator.  I am now reading 14.75 volts and cars will run with negative post off. 
Now I have a few hours of running new wire to get rid of all the splices in the existing wiring.
thanks again for you help.
Bob
  Reply
#7
It looks like what you actually have is a 2G alternator. While they are an upgrade to the stock alternator, people have had problems with them. Here is an article on upgrading from a 2G to a 3G.
http://www.mustangandfords.com/parts/mum...r-upgrade/



“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
  Reply
#8
Here's how a 2G should be connected

[Image: 2-G-ALT-wiring.gif]



“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
  Reply
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