Canon 5D Mark III Mirror Locked Up and Not Responding

[Jason88]

Help! I'm on vacation and my 5D3 just locked up and won't respond.  I removed the battery and tried a different one but nothing is happening!

There are no active lights or error codes when I change batteries.  They are fully charged.  Last thing I was doing was taking a video.

Any ideas?

Worst timing ever.

[Bennymiata]

Is the rotating switch around the live view button turned ot the left?
If so, it still thinks you want to take a video and hence the mirror is up.

Turn it off and see what happens.

Even with the button switched on, it will still take photos but will act as though it is in live view.

Otherwise, you may have to remove the main battery AND the small back-up battery to re-set the camera.

[Jason88]

The camera doesn't respond to battery removal.  Pretty sure something catastrophic has occurred. 

I removed both batteries.  There's no indication of a self check when the doors close.

[bkorcel]

I know it seems silly  but you should call canon ASAP. Pull the batteries, pull the memory cards.  If you are using a battery grip remove that and replace the camera battery door.  Try using one battery in the camera.  You have to have the battery door installed or it won't power up.

If you have a computer you can try hOoking up the USB cable and see if you have any sign of life.  If all fails the you will need to call canon.