Paul, I took mine to the local repair shop because of camera not focussing up close. They replaced it and it was all black like you report, they tried another camera and had the same problem, also they mentioned that it was overheating. They then put back in my old camera and it's got picture again but still not focussing. They said the main board must be faulty and wanted to post it away for repair. I suspect they're using a dodgy aftermarket camera replacement.
iPhone 5s 后置摄像头更换
