Rodney, we have exactly the same model although mine does not have the little heat shield in the instructions to which i've created a link below. I didn't end up replacing the I/O board. I played with it until I determined the only thing wrong was that it was shorting out. First, if you know someone with exactly the same model, have them charge up your battery and if your computer boots up fine, then you know for sure it's not your logic board that is bad and that it's most likely your I/0 board that's faulty.
Once you determined that, i used the ifixit directions to remove the I/O board and then, created my own little gasket out of electrical tape over the magnetic piece of the IO device. I then without putting the computer back together, reconnected the I/O board cable (picture 22) and connected the power supply connection in picture 17. i also used a piece of electrical tape to cover the edge of the metal chassis so I could ensure while the I/O component would not short out should it happen to touch the metal edge with a current going through the IO device. This was taken off before i reassembled the computer.
I did not put the i/o component back into place because it was easier to test the unit when it wasn't reinstalled. When the light started to burn bright green, I knew it was shorting out somewhere. I then reinstalled it and found i had a faint green light again and knew i had to take the unit apart again and redo the procedure until I found the short and finally determined that the little grey gasket on the magnetic end of the I/O device was not doing its job and I took it off and built my own little gasket out of electrical tape.
MacBook Pro 15" Core 2 Duo Modelos A1226 y A1260 Reemplazar Cable Placa E/S Izquierda
I was pleased because the repair shop I took the item to said it was a logic board problem and the logic board would have to be replaced which would have cost more than the value of the computer. Hope this helps and if anything I wrote is unclear, please tell me and i'll try to rephrase it.