I recently replaced LCD and digitizer screen on Ipod 4th generation. I got it to power up before I put the heat plate on to make sure it was going to work. I went back to put heat plate on and closed it up and got nothing after that. I thought maybe the batter needed to charge so I plugged it in and got the battery charge sound, but no picture. Itunes does not recognize it when I plug it into computer. Another question I have as well is that there is a white mesh sponge (very little) that you're supposed to transfer from the old screen to the new one that adheses to the bottom of one of the cables. Is this a vital step or can it be left out???