Electrical Issue

[ChicagoS14T]

So everything was going fine until..... we took her out of the garage and then we noticed a slight issue. Basically what ended up happening was the windows kept going down slower and up slower and then the lights on the dash got dimmer and eventually the car died. THen it didnt have enough power to crank up. So the issue now is: Is it the battery that was sitting in the garage for nearly 2 months or is it the alternator. I charged up the battery overnight so I will try and install it today and see whats up but im afraid it could be the alternator. What do you guys think??? When we got the car running we disconnected the positive terminal and the car died right away, so it looked as if the alternator wasnt producing power. But then someone told me that on nissans it has a built in voltage regulator which explains why the car just dies without a battery??? I dont know whats up and im waiting for a friend who has more experience with this, im a noob. Can anyone help out??? Any fuses worth checking?? We checked a bunch and they seemed fine.

[onosqv]

it's been sitting for 2 months, your battery probably is old too.

Just charge her back up and you'll be fine. Once she starts, you can check w/ a multimeter to see if the alternator is working - basically, if it's below 12volts w/ the car running, you have a problem. If it's 14volts or close, then your alternator is working fine. if it's somewhere in between, it's probably because you have accessories running (but you are fiine).

Pays to have a voltimeter for times like these, hehe.

[nismofly]

so you had the car on when everything slowly died and then the car shut off or the ignition was off?

if the engine was on its alternator, the car is running off it while its on, what you saw was the engine running off of then draining the battery while it ran then finally dying

[ChicagoS14T]

thanks for the replies... i went to autozone checked the battery out after charging it over night and it was good. So i went out and bought an alternator from a place by my house that does alternators. A few minutes later she seemed fine. So far so good. The SAFCII which I have is showing the voltage of the battery going up once the car runs a while so im guessing its charging the battery. And its a new alternator so everything should be okay now!