Default [Q] Screen stopped working, digitizer still okay

Around 11PM last night my phone's screen suddenly just stopped "turning on" - I recently had to replace it but it's been perfect in the last month. The digitizer is still registering touches and I can hear the clicks and notifications, just no screen.

Can anybody tell me which cable is the one that feeds the signal to the screen? I've torn it apart twice now to the same result. Tried gently "bending" and wiggling the phone with the back off hoping to see something pop up on the screen but no dice.

Thanks all...it'd be great to not have to buy a new phone.