Is this a four CDMA or an AGM? It sounds to me like you got the speaker on upside down you might need to turn it around and make sure the two prongs are hitting the leads and if that does not work then you must the damage something in the speaker and removal of the PowerFlex cable or you could a got a bad power flex cable that does happen some Times
Question one did you drop the phone? And if it suddenly just stopped working in responding sounds like the LCD digitizer has gone bad and needs to be changed out.
When you change the body of the phone out did you take all the little small 80 bitty washers out as well and transfer them over to the new body? They're really micro small washers underneath your motherboard the charging port act
Well for one I've seen some card readers with broken prongs on them start there and see if there's anything broken, and most likely something got burned out in the reader somewhere in the midst of doing the water repair
Take it to your local certified cell phone repair shop and let them do it unless you have experience with doing Apple iPhones in buying your parts off of Amazon or eBay they're not going to be OEM parts chances are they probably won't work it's a 50-50 chance but just take it to your local cell phone repair shop it's a lot easier
Sounds like An antenna problem with your network antenna inside the phone if you have access to a Pennelope screwdriver open it up and check your antenna plug-ins
Your plug-ins could be not properly plugged in all the way that's a very common problem with the 6+ because the plug-ins are so long, however you did mention that was dropped so it very much well could be something in the motherboard causing it to do all this ! But for the most part I would start in with the plug-ins
It's a very easy process you have to have a heat gun and you have to be very careful not to burn it up in the process while heating the sticky tape that's holding the back of it on! Use a guitar pick bike tool to work the edges around until the back glass starts lifting off
Did you try doing a soft reset on it? Try doing a soft reset on it first then see if the cameras come up working! If this does not work try new cameras front and back, and if that is not working then it is water damage problem if there's any kind of corrosion around the plug-ins most likely that is your issue
