Alternator Light Won't go off
#11
Batteries might work.  There is also one of those 6V square shaped batteries for flashlights.  If you try batteries don't forget the ground.  If you have an extra ballast resistor, you might be able to go though one to the + side of the car battery.  I don't know if you will get enough current from a little 9V battery.
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#12
I finally fixed it.  I had a spare mower batter and took the positive and connected to stator and other to ground while alternator was running.  The dash light would go off when i did this which confirmed i wasn't getting voltage from stator.  I then opened up the alternator and cleaned the part where the brushes make contact. it was pretty black. I'm not 100% sure that was the issue but when i put it back together it all worked and alternator light went out.


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#13
Way to go nice fix. It's amazing the multitude of car problems, that are solved by simply cleaning connections, and grounds. 

JTS
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#14
Nice work!  Glad to hear it's fixed!  Now you have a good understanding how the ALT warning light operates.

After all of the back and forth, I suspected the STA voltage coming out of the alternator was too low or non existent.  Although, I will admit, I haven't seen that issue before when the alternator still charges correctly.

If you can, also check the diodes when you have the alternator opened up.  Just to be certain all the internal components are okay.  With one or two bad diodes an alternator will still charge okay but not to its potential.  However, if two or more are bad, t will drain the battery when the engine is not running.  If you couldn't check them, if there is no drain on the battery, they are probably okay.
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