Err 01 - The communication between the camera and lens is faulty.

[David Parsons]

This seems to be quite common on 24-105f4, (Google search), I found out when it happened to me in June.... contacts all OK, only that lens, commonly seems to be when aperture motor (or connecting ribbon cable) is getting old and tired. Looked at trying to fix myself, but U-tube videos convinced me I would have a few small bits left over, so got it done professionally (£160) - seems OK now, so could it be the same / similar thing with your lens, my 24-105 is over 10 years old? Note was told short term work round was to use AE and f4 (fully open so motor not needed...) obviously not a long term solution

 

[tonyjr]

If same problem on different bodies , probably contacts on lens .

I prefer a cotton Q-tip with nail polish remover to clean contacts on lens .

You can also go to a best buy , fry's any place that sells bodies and try

on a new one .

 

[safford1977]

Took me a while to remember I posted the question here but I found a repeatable solution. I found a mention of odd errors when using generic batteries - which I intermittently use. I tried a Canon Battery in both the Mkiii and mkiv bodies I have but still had the problem. I then got the idea to remove the generic grip (I have one for each body) and the problem on both bodies went away. I had gotten the grips from B&H, they're the Vello brand sometimes bundled with bodies. With the LP-E6N batteries I haven't had an issue running out of juice even for all day event photography. I miss the vertical grip but after reading bad reviews of how cheap the Canon one is on the Mkiv I'm just going to get used to shooting verticals the old fashioned way.

 

[tonyjr]

FYI - I have a 7 d with the 2 battery holder .

Now I carry the one that takes AA batteries .

 

[KScheyEOS]

I had this problem with a Tamron 28-300mm lens. I contacted tamron and they told me it was a bad aperture and it would run me $250 to fix the lens. I just bought a new upgraded lens and the replacement works fine.

kevin

P.S.: I was using a canon EOS 6D and the error occurred while I was taking photos with the aperture shut down between f14-18