Canon 5D Mark IV is have a communion err with my 24-70 and won’t focus

[AshelyA02]

I have a canon 5D Mark Iv. I got an error 01: “Communication between lens and camera is faulty” with my 24-70 mm lens. I read to carefully clean the gold contacts with a lens cloth. I did and tried it again and got the same error. I tried a different lens and it connected fine, but on live view it only worked on MF. When I tried AF mode, it wouldn’t focus using the back button or the shutter button. I doubled checked all of my settings and everything is set where is should be, so I’m wondering if it’s both my lens and camera?

[p4pictures]

If you have another lens, or can borrow one then try that. If the other lens works with no error then it's your 24-70mm that is at fault. If the other lens you try gives the same error as your 24-70mm then it is possibly the body.

[AshelyA02]

Thank you for the response. The 24-70 mm lens had the Err 01. When I tried a different lens, it connected okay, but my camera wouldn’t focus at all on live viewing with any of my lenses.