Voltometer Reading
 

I put a new battery in my car after the old one apparently died (it was a Sunday and I had my son for the weekend and just bought a new battery to get him to his mother before she threw a fit). I would have liked to have had the old battery checked but couldn't. Anyway, since putting in the new battery, the voltometer usually reads between 12 and 14 (I think the top number is 18). It also moves up when I rev the engine. Is this a good sign that my alternator is working? I don't want to do that old school test of removing the pos wire as my manual says not to and you guys told me I could fry some computer components. So, does it sound like my alternator is working and my battery really just crapped out on me?

Thanks

Scruffboy

if it moves when you rev this sounds like its working to me if it stays above 12 and below 14+.. Do not do the "pull the battery terminal off test" i agree this is a bad idea... i dont have a voltage gauge, but i can hear the alt. load up and slow the rpm's a little when i turn on the headlights or the heater on... and it frees up when i turn back them off..

Voltage Reader question
 

How would you use a voltage reader to check the altenator. It seems it would be easy to use to test the battery, but that would not tell me if my alternator is working, as I'm sure a new battery is going to hold its charge for a little while. Where would you place the terminals and what other things would you need to do to check the alt. I may be able to borrow one.

Thanks

most volt meters have a red and a black lead, red goes to positive on the battery and black goes to negitive side of the battery..

they try to keep the voltage steady at 13 - 14.5 V all through the rev range. your altenator is stuffed, or the belt is very loose. but i'd get it fixed by a pro, there's nothing in there you can fix yourself without buying enough tools to pay for the pro's time anyway. doesn't sound like brushes, prolly diodes or regulator.

here's another test ;
lights on, engine off -> lights on, engine on. and are the lights any brighter now ?