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GRRRR -- Dead in the water again!!

GaryBeu

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Guess we had too much fun driving yesterday. Came in last night and the alternator light had burned out (was a new bulb). Replaced it this morning and now IT WON'T GO OUT. I have 12.5 volts at the battery with engine NOT running. I have 12.5 volts at the battery WITH the engine running. I have 12.5 volts at the brown wire on the alternator with my multimeter grounded to the frame and when grounded to brown/yellow indicator terminal. I guess the alternator went "Tango Uniform" but how do I test that? If bad, do I just buy a new one or can I repair it? Any suggestions? Thanks
 
Take the alternator into a PepBoys/NAPA/Autozone/O'Reillys/Advance Auto - They can test the alternator for its charging capabilities.

The fanbelt is properly taught, right?

You can replace the diode packs in the alternator if needed...or any automotive electrical shoppe can do the same if the alternator is FUBAR.
 
Yup, what Rick said.

Likely if you get no more than 12.5V with engine running (up around 2K RPM), the alternator is most likely the problem.
 
isn't the light bulb part of the circuit?
 
I think it is and...the second one just burned out. What's up with that??!!
 
you've got a ground somewhere, or a surge. did the second one last long enough to get a voltage reading with the car running? enough that is to see if the alternator is working properly.

not sure where the short would be - except clean all the connections to the alternator and, check where the bulb comes to the dash. (Is that a metal dash?) if so, is it touching the dash? If so, I don't think it should
 
is the lightbulb the proper voltage?
 
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