Help: Altenator or Battery...which one?

e34play · #1 (**permalink**) 10-21-2003, 11:05 PM

Is there any easy way to check if my Altenator is working correctly?

Here's what happened. Two days ago I left my lights on and drained my battery. I went an bought a battery charger, and let it charge for 6-8 hours.

Today my battery was flat again.

My thoughts:
1) Altenator is not charging battery
2) Battery is not holding the charge because it was drained so low

Is there anyway to test the Altenator by myself?

petar7408 · #2 (**permalink**) 10-21-2003, 11:46 PM

you bought a battery charger but not a new battery??? either way you do need a new battery, so i would replace it first and see how it holds up

e34play · #3 (**permalink**) 10-22-2003, 12:34 AM

Quote:

Originally posted by petar7408
you bought a battery charger but not a new battery??? either way you do need a new battery, so i would replace it first and see how it holds up

Yeah...$25 (charger) vs. $115 (new battery)

Why get a new battery if mine's ok?

L8APX · #4 (**permalink**) 10-22-2003, 10:33 AM

You can check for the voltage output of the alt at the positive lead off the back. Use a voltmeter and it should put out 14.X to the high 13 volts.

This test takes about 5 minutes and an Autozone or Pep boys will do it for free.

Interstate batteries are good replacements and alot cheaper than OEM.

WarpedE36 · #5 (**permalink**) 10-22-2003, 11:18 AM

same thing happened to me.. went to pep boys and they tested it.. i got a new battery..

of course my atlernator went a month later anyway but it didnt have anything to do with the battery