Charging port not getting recognized.

So my iPhone 5c is not recognizing when I plug it in. I thought it was it a bad charging port, so I replaced it. That didn't do anything. The headphone jack works and so do the loud speakers. I then took out the motherboard and put it in a full functioning iPhone 5c which I tested (charging port worked as well) but this motherboard failed to recognize when it was plugged in and wouldn't charge. The phone worked perfect from the remaining battery power it had, but since the phone couldn't charge. It died on me and I either have to put a new battery in it, or switch the motherboard back so it can recognize when it's connected and charge the battery that way.. I'm pretty sure this has to do with the motherboard, but I'm not for sure. Any recommendations?