I have the same problem. Its only the autofocus. It seems to deactiviate autofocus as if it is in manual mode but you still have the AF frame and cant take a photo. Sometimes it will take a photo just out of focus but is very hard to even do that.
It happens tome a lot. I am an event photographer. I found this post on google. It happened a ton of times during one party. I didnt know if my lens was broke or it was the camera. I took the lens off a bunch of times to fix it and I turned it on and...