Alternator? Belt?

I have a '97 Rodeo 3.2 w/new battery. The voltmeter reads a constant 12v regardless of what the vehicle is doing. When the rpm's go below 1000 the dash lights (brake light, battery light, 4wd indicator, etc.) go on and the blower motor kicks off. Once I rev above 1000 the fan goes back on and dash warning lights disappear. The alt belt squeals upon initial startup. Is this an alternator gone bad, or just a belt that needs to be tightened? Both? Neither? Any help is much appreciated! Thanks!

I have a '97 Rodeo 3.2 w/new battery. The voltmeter reads a constant 12v regardless of what the vehicle is doing. When the rpm's go below 1000 the dash lights (brake light, battery light, 4wd indicator, etc.) go on and the blower motor kicks off. Once I rev above 1000 the fan goes back on and dash warning lights disappear. The alt belt squeals upon initial startup. Is this an alternator gone bad, or just a belt that needs to be tightened? Both? Neither? Any help is much appreciated! Thanks!
Tighten the belt until it stops squealing then see what it does. If it still doesn't charge you're likely in need of a new alternator.

Sounds like a bad alternator to me. Even with the belt squeeling it should still put out 14 volts. Since the belt has been slipping replace it along with the alternator.

I had the same problem when I replaced my alt with a bosch remanufactured unit. Turns out it was bad right out of the box. Hopefully you'll have better luck. Get the oem part if you can afford it.