I keep having this issue where my (Electric volt meter I think its called? I dunno, the one with the battery on it) keeps falling down to 13 at times, normally when im sitting at a red light. I heard that if it drops past 13 that it could most likely be the alternator. Is that true? And if so, how much will it cost?

 

anything about 12.6 is considered charging, but if it fluxuates with rpm, the alternator could have problems such as a diode or stator winding burnt up. id check it with a digital voltmeter directly at the battery, since the gauge could be bad. or if you have access to a carbon pile load the battery down to 12.6 and see how many amps the alt is putting out with a amp clampfrom the cable on the back of the alternator

 

i meant to say anything above 12.6 is charging.... as for cost.. depends on the alternator. check out rockauto.com good site

 

What year is the car? On older cars you could disconnect the battery while the car was running, and if the car dies you needed a new alt. newer cars have computers that might get messed up with the electrical spike that might occur.

 

i never did like doing that, as running an alternator in an open circuit would cook it. right out of a 2300 page auto tech book.

 

When I was 17 I had a Chevy 1 ton tow truck, a 1961 with a 348, I had problems with my alternator and to me it was just beyond me what a field was to an AC generator so I grounded it thinking like how we had to polarized a regular generator, plus I disconnected the battery and turned on every light on my wrecker.


Blew every one of them out.

Of course I later learned you can get 110volts from an alternater easily and that was pretty much what I had done! Nowadays I raely even jump start anything because of the amount of electronics in the new vehicles, if the other had a bad short it may very well hurt your vehicle. Its safer to use a portable battery made for jump starting.

 

I have a 2001. Another thing is that sometimes my CD player will just shut off and wont turn back on. Possibly another sign?

 

sounds like a ground issue.