Replaced display assembly not working
I just replaced the cracked display assembly of my MacBook Pro 15" Mid 2014. After turning on the MBP the screen stays black. I have checked all motherboard connections as well as the brightness and performed a SMC reset.
I then put the display assembly on another MBP to confirm the screen is working and it is on that MBP. So I know the display assembly is 100% ok.
To confirm there is no problem with the MBP itself I put back the cracked display assembly and it is working (although cracked).
So it seems I have a working MBP and a working display assembly. However when they are combined the screen stays black.
What am I missing here? Does anyone have a suggestion or idea?