02-23-2017 05:14 PM
Hi, dear collegues!
I have the problem with my quite old 7D. Few months ago it stopped autofocusing when shooting through the viewfinder (and it works fine if I switch to Liveview). And it's not only stops working when I switch to viewfinder, it's showing Error 40 and I can't switch the camera off or on until I remove the battery and install it back.
My lenses are Canon EF 28-135mm f/3.5-5.6 IS USM and it works fine with other cameras, so it have to be the body problem.
02-23-2017 05:30 PM
Thanks for posting in the Canon Forums!
An Error 40 is a power source malfunction. It means that an internal error in getting power from the battery to some part of the camera has been detected. It could be caused by a weak battery or a third party battery. We recommend trying a fully charged geunine Canon battery in the camera. If that does not clear the error message, then the camera would need to go in for service. If you are in the United States, you can set up a repair HERE. If you are outside of the United States, you can find Canon in your country HERE.
We hope this helps!
02-23-2017 07:37 PM
Thanks! I'll try to change the battery tomorrow.
It's just seems odd to me that there are no problems at all in shooting pictures and video with MF-lenses and the problem only occurs when I attach AF-lenses and only when I shoot through the viewfinder. I were hoping to find someone that used to have exactly the same problem and yet found the right answer to share.
02-24-2017 03:39 PM
02-24-2017 10:45 PM
Thanks! I just discovered that there are two AF-systems in my camera, so- you're right, I think. Anyway, the body is in the service now, so soon I'll know for sure.
02-25-2017 03:32 AM
05/31/2023: New firmware updates are available.
EOS R6 Mark II - Version 1.1.2
05/18/2023: New firmware updates are available.
EOS Rebel T100 - Version 1.1.0
EOS 5D Mark IV - Version 1.4.0
EOS 6D Mark II - Version 1.2.0
PowerShot Elph 360HS - Version 188.8.131.52
PowerShot SX420 IS - Version 184.108.40.206
PowerShot 620 HS - Version 220.127.116.11
PowerShot SX720 HS - Version 18.104.22.168
PowerShot G1X Mark III - Version 22.214.171.124
PowerShot G7X Mark II - Version 126.96.36.199
PowerShot G9X Mark II - Version 188.8.131.52
04/20/2023: New firmware version 1.4.1 is available for EOS R3
03/30/2023: New firmware updates are available.
EOS 1DX Mark III- Version 1.7.1
Speedlite EL-1 - Version 1.0.2
03/30/2023: Product Advisory for EF50 F1.2 L USM
03/30/2023: Product Advisory for EOS R10
2/07/2023: New product announcements!EOS R8 EOS R50RF-S55-210mm F5-7.1 IS STMRF24-50mm F4.5-6.3 IS STMRF15-30mm F4.5-6.3 IS STM
Canon U.S.A Inc. All Rights Reserved. Reproduction in whole or part without permission is prohibited.