9900 Problems! Please repl!

Hi there. I have fixed lots of blackberrys before and have never had any issues.
Blackberry Bold 9900 with a cracked screen. I replaced the entire display assembly (the digitizer/lcd mic) everything all in one so all I had to do was install it. I have double checked the screen codes and they match. I put the phone back together and I'm getting a blank black screen. Almost like its a black plain screen but its lit up by the backlight. The lights on the keyboard work and currently the LED on the corner of the phone was flashing green. It appears the phone is working but I can't see a damn thing on the screen.
I reseated the ribbon cable twice and from my knowledge, wouldn't it show a white screen if the ribbon cable was loose? Cause its a plain black screen. What does that mean? :(

Did I get a faulty screen???? This is a work phone for a friend so its urgent.

I don't know anything about repairing, but I can tell you a flashing green LED is NOT normal...
Do you personally use a BlackBerry? This is your first post in Crackberrt, so I'm just wondering how much you actually know. Your profile shows you use iOS devices. BB's are a bit more intricate hardware wise, in terms of hardware, and NFC, just to name a few, in comparison to iOS devices. Not the best idea to do it yourself if you're not an expert on this, because you just broke your warranty. Mind you, the 9900 from what I know is a bit more complex than older BB's.
The green LED is most likely an indication that you did something wrong..., unless for some reason your friend's phone flashes green instead of red.
Plug the phone into a PC and see if it recognizes. If it doesn't, you've probably screwed something up big time, and should probably contact BB to sort it out.

Haha..the green LED I remembered after just has something to do with how you have wifi coverage or something. Not a big deal but I must say, your post was pretty doomy :p

Trust me, I have repaired blackberry bold 9900s and other models without a hitch. I also fix iPhones and computers for a living so I'm pretty familiar with this stuff, yet I have not ever seen a blank black screen so I was just picking other peoples brains! I'm pretty sure I got a bad screen. It seems like the only thing working is the backlight. I do not personally own or use a BB so no I'm not super familiar with the LED flashes and other things but a little research confirms that the flashing green LED shouldn't be anything to worry about.
Flashing LED color descriptions - BlackBerry Bold 9900/9930 Smartphones - User Guide - BlackBerry Bold Series - 7.1