I used istat pro to help indicate my battery was not holding a charge very well. I looked up all the correct information and bought the correct battery for my computer online.

After properly shutting down my computer I followed all the steps on this website to replace the faulty battery for the new one. After reassembly the computer won't boot whatsoever. No sound no picture no fan, nothing. Even when using the old battery it still won't boot. The battery indicator on the side indicates there is battery and when plugged in with the original Mac power cord the light on the MagSafe is green.

Is this a logic board issue? Did I messes something up?

What can I do to fix this?