Alternator?
 

On the drive home from work my battery light came on and it dropped to 12 volts. By the time I got home it was down to 9 volts, blinkers were barley working but I made it. I thought it was the battery because my current one was old so I switched it with a newer one. Now it stays at 12 volts, won't drop below that even if I drive with anything on, but it won't go above it either. Did I put a battery that's to small in? I have no idea what the amps are, there not labeled. Or is this a sign of my alternator going? Thanks.

i have a new battery and a new alt and it stays at around 12 volts, however i am not sure there isn't something wrong with my system...just my :icon_twocents:

Is your battery light on? Mine has always stayed at 14 volts, can't remember if it was the same with my Blazer...

My guess would be alternator. Mine outputs about 14V. I image the battery could continue outputting 12V until it is nearly drained.

Well I guess tomorrow after work I'll try my alternator from my Blazer, hopefully that works.

Dammit, an alternator from a 95 blazer doesn't quite fit, go figure. Well I guess I'll take it to get tested. Will post results.

It's your alternator for sure,don't even bother testing it.
Do youself a favor and buy a brand new one(not a remanufactered)if at all possible.
The remans just dont seem to hold up any more. A new one cost me about $125USD
about 6 months ago. Good Luck!

Yeah, I got it tested, sure enough it was hooped. Going out to buy another one later, $165 with trade in, so not to bad. Just sucks about the Blazer alternator, it's working just fine. Oh well, time to part out the Blazer and get a bit of cash.

Well I put the new alternator, put in a charged battery, turned the key and nothing. No power, everything is grounded, the battery sparked when I connected it, so now WTF? Is it possible to fry my electrical system without a battery? I even tried my older battery and the same result.

Well I had a second look and my and my infinite wisdom hooked up some ground cable to the alternator, and left the power cable off. I noticed it and switched it with the power cable and still nothing. Put the battery in a car and it fired right up, so I know it's not dead. Where does this ground cable go? I connected it to a few spots. It ties into a fatter cable that goes to a few other places on the engine.