Why won't my screen turn off after glass repair?

[nvdolfan]

screen won't turn off after glass repair

I just replaced the cracked glass on my daughters S4 and now the screen won't turn on.
When first powered up the screen lights up a dark green/blackish color for a few seconds and then turns off.
I have not actually glued the new glass on yet, was trying to test the phone first and leave the glass just resting on the phone so that I can pull it off and troubleshoot.
The phone powers up normally (I can tell from the sound) and it appears the touch features and buttons work as well (again, from the sound).
I've even able to call the phone and talk on it.
Since the screen lights up initially I was hoping this might be salvageable, but can't find find anything on google with this symptom.

Things I've tried to no avail:
Booting in recovery mode (volume up and power)
Pulled the battery
Disassembled the phone and disconnected/reconnected all the connections
Put the cracked screen back on

Any ideas on things to check? Many thanks in advance!

 

[nvdolfan]

Re: screen won't turn off after glass repair

Doh! Title should obviously have been screen won't turn ON but I don't see how to edit the title. :-(

 

[blakechan1989]

Re: screen won't turn off after glass repair

Seems something wrong with your display. Did you bend the flex cable during the repair process? The most commen reason why your screen is black is because you've damaged the flex cable unconciously during the process.

 

[Newsteel]

Re: screen won't turn off after glass repair

Or the connector of the cable or the one on the logic board. That is very common if you push hard when it's not aligned properly. Another reason, and believe me it's verrrry common is a bad new part.