transit 6000cd wont turn on?

My transit 6000cd tuner wont turn on ever since i took it out to get the serial number to obtain the code i never unplugged it but i did take the security panel off but now it wont even light up. It just seams dead! the fuse is fine. I have since unplugged it and plugged it back in again but still nothing? The enter code timer was on 3mins odd last time i saw it? Any ideas what it could be?