so what exactly is a pcm and what does it do and were is it located at

 

I Guessing a computer computing chip. I looked it up and this is what I got:
pulse-code modulation- a form of modulation that transforms a wave-form, as an audio signal, into a binary signal in which information is conveyed by a coded order of pulses for transmission, storage on a disk, or processing by a computer.

 

The PCM is your Power Control Module. It is one of the computers located on the driver's side by the intake airbox. It controls.....wait for it........the power distributed throughout the car. It's most common job is to tell the alternator to charge the battery as the batteries voltage drops throughout the run time. It also sends pulses to the injectors, spark plugs, and so on. It relies on several sensors to do all of this though, so it's not self dependant. This also means that it shouldn't be the first thing to blame when the lights don't come on, car doesn't start, or battery isn't charging.....and so on.

 

So basically the ECU and PCM is one in the same. In that other post they made seem like it was other computer inside the car.

 

The PCM is in the engine bay closest to the airbox.
E ngine C ontrol U nit = P ower C ontrol M odule in this case they are one in the same.
There are a bunch of "ECUs" in our car one of them is the ABS-ECU which is found on the floor board on the passenger's side.

 

i replaced my battery and cheacked my atl they were fine so this souned like what was goin on with mycar so it was my next guess..

 

I would go to a shop that rebuilds alternators because they know what to look for. Autozone workers, for the most part, deal with parts and usually have no clue...no offense to the ones that do.

 

witch one is it the first one or second one?? idk how to post a pic so her it the site. http://www.cardomain.com/ride/2131265/3

 

My books say the front one right behind the fuse box.

 

Do you have an automatic?