I am having trouble getting a signal from my Phantom 3 4K. it has been crashed, and I thought repaired.  In DJI GO it reads Disconnected at the top of the screen. I have tried linking through the app and it tells me to confirm the frequency configuration. All the channels seem weak. I'm not sure what to do next.

I removed the gimbal. Can I link the aircraft and controller without the Gimbal? I've seen instructions for other models, but the controls are different. I'd like to at least like to rule out the gimbal repair as the source of my problem.

One of the rotor arms flexed in the crash enough to cause the seam to mis-align. I popped it back into place. I don't believe I ever took the cover off. Is there something inside that is likely to have popped off afecting the signal?  

I am familiar with UAVs, after flying RC for several years, and building a few quads from parts. I don't know much about DJI. Forgive me if I am asking the obvious. I bought The Phantom 3 4K many years ago. Flew it twice. A prop came off ending the second flight abruptly. It sat for a couple of years before I got around to replacing the broken gimbal arm and ribbon cable. When I got the gimbal back together. I vaugely recall hovering it in my house. It seemed to work alright. By that point all the FAA restrictions had convinced me to stop flying anything. There were just too many things to worry about. I'm just getting back to it.

Hi, droidling. Thank you for reaching out and we're sorry to know about the incident that happened to your aircraft. In this case, we highly recommend sending the unit in for proper diagnostics. As we don't recommend fixing the drone alone since we can guarantee that it will work properly or I'm afraid that it might get worsen the issue. You can contact our DJI support team at  https://www.dji.com/support for us to set up a case. Thank you for your understanding and support!