Yeah, I appreciate it. I took the battery and fully charged it, let it sit overnight and tested it 24 hours later, I get 12.1v, and I'm not certain the battery is good still.

 

Hi Andy,
If you haven't tried it yet
If you hook up the battery,turn the headlights on for a short while ,maybe 30 seconds, then check what your battery voltage reads. It should still maintain at least 12 volts.
If was fully charged and did not maintain that voltage, I would consider replacing a battery that could be on it's way out.

 

after 48 hours sitting unhooked from the car after fully charge it reads 11.5v. I'm replacing the battery.

 

New vehicles these days require that the PCM be notified of a battery change and a scan tool is required to do this You might want to check if a local shop can do this for you.