Won't charge battery, magsafe stays green.

I run a small computer repair shop and have done hundreds of repairs in practically every version of every Apple computer but this one has me stumped. Customer came in and the computer laptop would power on and everything would work except the wifi and the fan was on full blast constantly. Very annoying.

I popped it open to find that the previous shop working on this computer LEFT THE HEATSINK OFF THE CHIPS! Since the computer still worked I powered it down, ordered the heatsink and installed it. When I got everything back together the magsafe no longer lights up for more than 2 seconds if at all. I removed the dc-inboard and gave it an alcohol bath and re-flowed the solder and now it lights up, but stays green and doesn't actually charge the battery. I'm completely bewildered and would appreciate any help or diagnostic steps!