Heya fellow POTN
Just got my camera back from canon to clean the viewfinder having a fibre in there that was annoying. Long story short it didn't get fixed. I've purchased the 100-400 II while it was away and when I got my camera back, mounted it for the first time. Once I've selected AF cross point only, my side AF across points all disappear. It comes back if I use 61, 15 or 9.
I've tried switching lens 24/70 F2.8 II, 85L, 135L and the 200L and they all came back. It only seems to be a problem with the 100-400 II. Any ideas? Did Canon knock the mirror or AF module? Thanks for reading.