2001 4Runner - today my check engine light and vcs lights came on. It started back up no problem and ran fine for the ride home, but the lights stayed on. My neighbor came over and the first thing he did was clean off the corrosion on the battery terminal. After he did that, my car had no power at all. Nothing. There was a little clicking coming from the fuse box but I couldn't even get it to go into neutral. He then jumped it, and full power, no problem. As soon as I turned it off again no power. Another friend came over and tested the volts on the battery & it seemed ok. We went to autozone & again...nothing. But when they put a charger on it, it runs fine. So what could be causing this? I'm at a loss. It can't be the alternator because after it gets jumped everything has full power. My battery is only a couple years old. Autozone ran a diagnostic but it read that there were no codes. Please help 
