I have the same issue with my MacBook Air (11-inch, Mid 2013) [ MacBookAir6.1 ] running macOS X Sierra (10.12.2)
Apple Hardware Diagnostic (AHD) shows the camera and no errors on the extensive testing.
System Information -> System Report ->
- Camera : shows "No video capture devices were found."
- Diagnostics:
Power On Self-Test:
Last Run: 2017-01-15, 11:11 AM
Result: Passed
FaceTime App shows "No camera available."
I've rest SMC, PRAM, and all the standard resettings recommended by Apple.
I just reformatted OS X and checked to see if it was something I did on software side, and yet not fixed. So if the problem is software, it's with Sierra OS X 10.12.
I just don't understand how come AHD sees the camera, but the OS X does not.
I'm this close to abandon Apple and install Microsoft windows or Unix on the machine to prove the problem is with Sierra! Very Frustrating!!!
Can anyone help?