5dIII AF point problem

Folks,
I have a problem with my 5dIII. It started at a wedding over the weekend without any identified cause such as a drop or splash. One of the AF points (2nd from the top, first row left of center) is randomly blinking in landscape orientation. When I turn the camera to portrait orientation, the blinking stops. Turn it back to landscape and the blinking returns. it happens both in red and black--push the AF selection button and the whole array turns red, with the blinking AF point, and also when its back to black. Toggling the M.Fn button doesn't seem to rid it, either. I pulled the battery and that got rid of it for a little bit, but then it came back a few minutes later. AF works with both this problem point as well as with all the points around it, but its annoying and makes me wonder if something bad could be coming down the pipe.
..Anybody?

The first answer is probably going to be the same as any other electronic item, try a full camera reset, settings and all, to get it back to factory base settings. See if that fixes it, then go back and reset the settings to what you need.

Ok thanks. I've forgotten all I've done to really tweak it. I haven't done any manual focus adjustments or anything particularly difficult, but have customized a lot of menus and settings. If nobody else has identified this particular problem before I may have to do that.

It sounds like you've just memorized that point as a preferred AF point for easy recall. It is part of the AF system on the 5D3.

Here is an article from canon that describes what you are seeing in the viewfinder as well as how to program or clear the point...


http://learn.usa.canon​.com …emorizing_af_po​ints.htmlp

Exactly that is what I thought about too. I use that feature all the time on my 1DX.

Certainly sounds like it...

Thanks all. I certainly didn't go into any menu to set a point as an AF. I think when it happened I was toggling the M.Fn button and perhaps my spastic fingers magically entered the secret combo of buttons and it set the blinky point.

Canon was quick enough to answer my phone call and unfortunately this particular rep was quick enough to push me to resetting everything, which did get rid of it, along with all the rest of my settings. the audible "beep" was on with auto focus and BBAF was disabled. Easy enough to reset. I hope didn't miss anything else

You don't register an AF point in any menu, but by pressing two buttons at the same time. Exactly which buttons depend on the particular camera.