Ani Svadjian

Have you tried turning the phone on in Safe Mode? If you open your phone up in Safe Mode and you are able to receive calls, then it is most likely a software problem. To open your phone in Safe Mode: (1) Turn the device off. (2) Press and hold the Power key past the model name screen appearing on the screen. (3) Release the Power key when "SAMSUNG" appears on the screen. (4) Press and hold the Volume Down key immediately after releasing the power key. (5) Continue to hold the Volume Down key until the device finishes restarting. (6) Release the Volume Down key when "Safe Mode" appears in the bottom left corner of the screen.

What should I disconnect the wires with?

Our group had to remove 2 screws.

How many screws?

You are missing a step in between 10 and 11:

We had to remove four cables from the motherboard before removing it.