Screen is flickering with blue scanning lines

Hello everybody,

My iPhone 4 8GB AT&T screen was flickering at first, so I decided to take it apart and try to clean it up. The phone suffered from water damage a while ago, and I believe that corrosion had built up inside the phone. While I was taking apart the phone, I had to put a lot of pressure to take out a stripped screw (the iPhone was repaired by a bunch of amateurs). So, when I took apart the phone, I cleaned the phone up with alcohol (70%) and put it back together. When I put it back together, the digitizer worked, but the screen had blue lines moving side to side. Do you think that this is an LCD problem or a logic board problem? The backlight lights up when the power button is pressed. Also, does the ribbon cable and socket look damaged at all to you? I don't want to replace the logic board ($$$!).

Things that I have tried:

POWER + HOME to restart it

RECONNECTING the LCD and Digitizer ribbon cables

Making sure none of the pins on the cables and connectors are damaged

Please help,

Kevin

Also : I have included pictures so that you may see.

Thanks

The screen kind of looks like this when plugged in.