Q: MBP r13 built in iSight Camera LED always on

If you have added no third-party software since your MBPr worked properly, and

if your problem continues after you have tried restarting Mac, and

if no other relevant suggestions (test more than one user - do NOT use "guest" user for this test - account)

    from How to Troubleshoot iSight doesn't fix the problem, then

use the final "Troubleshooting" suggestion: "... contact Apple or an Apple-Authorized Service Provider for service."

Unless you have a current backup of your Mac, make one before rendering it for service.

If you have not tried it already, it is possible, though I think unlikely, that Reinstalling OS X Mountain Lion might correct your problem.  It will cost you nothing but some time to try.

Message was edited by: EZ Jim

Mac OSX 10.10.2

You're welcome, xiaopigu.

A simple restart often cures unexplained glitches. 

Because restarting is free, quick, easy, and often effective, it's the first thing I try when  troubleshooting a new problem.

Message was edited by: EZ Jim

Mac OSX 10.10.2