topic Re: Canon 40D Autofocus Will Not Work in EOS DSLR & Mirrorless Cameras

Canon 40D Autofocus Will Not Work

Greeblen — Sun, 15 Nov 2020 03:44:41 GMT

Hello there,

I have a 40D with the kit USM lenses that the autofocus stopped working completely.

The camera takes pictures fine with manual focus, but I'm trying to fix this issue so I can use it as it was intended.

Firmware version is 1.0.8

Some things I have tried to fix this issue

Reset to Factory Settings
Removed/Replaced the CR2016 coin battery
Used a bulb on the AF sensor area to clear any potential dust
Cleaned the contacts for the lenses and the camera

All to no avail.

I bought this camera new back in the day and have babied it and taken great care of it over the years.

The interesting thing is that a friend recently gave me a Canon Rebel XSI that is having the exact same issue.

Am I dealing with some sort of planned obsolecense here?

Thoughts and suggestions would be greatly appreciated.

Re: Canon 40D Autofocus Will Not Work

Waddizzle — Sun, 15 Nov 2020 12:44:54 GMT

What if you have one bad lens, instead of two bad cameras? BTW, make sure the AF/MF lens switch is on AF.

Re: Canon 40D Autofocus Will Not Work

Greeblen — Sun, 15 Nov 2020 17:02:55 GMT

I should have mentioned...

I have 2 kit lenses for each camera and I bought the 40D new in 2007 and have been very careful with both camera body and lenses over the years so I know they have been taken well care of.

I've tried all 4 of the lenses on both camera bodies and they all behave the same way (yes, AF is selected), so I am thinking this is a camera body issue, not a lens issue.

The camera tries to autofocus but won't take the pic, and the best way I can describe it is that it "stutters" back and forth trying to find focus but just can't get it. I have tried selecting/using the various focal points in the viewfinder, to no avail.

Re: Canon 40D Autofocus Will Not Work

MikeSowsun — Sun, 15 Nov 2020 17:05:10 GMT

@Greeblen wrote:
Hello there,

I have a 40D with the kit USM lenses that the autofocus stopped working completely.

The interesting thing is that a friend recently gave me a Canon Rebel XSI that is having the exact same issue.

Thoughts and suggestions would be greatly appreciated.

Please confirm.... Are you saying you have 2 cameras and 1 lens, and that both cameras will not AF with that 1 lens?

Re: Canon 40D Autofocus Will Not Work

Greeblen — Sun, 15 Nov 2020 18:41:48 GMT

As mentioned in a previous reply, I have 2 cameras and 4 lenses.

AF will not work properly on either camera body (40D and Rebel XSI) with any of the 4 lenses.

All 4 lenses will AF perfectly and perform normally when used on another camera body that is not experiencing this AF problem.

Re: Canon 40D Autofocus Will Not Work

Peter — Sun, 15 Nov 2020 20:01:29 GMT

You can try if AF works when using a remote switch.