AF (Autofocus) Does Not Work (EOS 5D Mark IV)

Check the Focus Mode Switch On the Lens

Autofocus will not operate if the focus mode switch on the lens is set to ⋖MF⋗.

Set the focus mode switch on the lens to ⋖AF⋗, as shown in the image below.

Clean the Lens And Camera Electrical Contacts

The transfer of information between the camera and the lens is carried out by the electrical contacts on both the camera and the lens.

Contacts

If the contacts on either the lens side or the camera side get dirty, communication cannot be carried out correctly, and in some cases the autofocus may not operate correctly. If the lens or camera contacts get dirty, please clean them very gently with a clean, dry cloth.

Caution

Mount the Lens Securely

Both the camera and the lens mutually exchange information. For this reason, if the lens is not securely mounted, there may be cases where the autofocus does not operate correctly.

Align the red dots on the lens and camera and turn the lens as shown by the arrow until it clicks in place.

Check the [Custom Controls] Settings

If autofocus does not operate when the shutter button is pressed halfway, the [ : Custom Controls ] setting may be changed as follows.

In this case, if the shutter button is pressed halfway, the camera is set to lock the AE (fix exposure).

In this case, if the shutter button is pressed halfway, the camera starts to meter.

In situations like these, please change the setting to [Metering・AF start].

Please see the Instruction Manual that is supplied with your camera for details about how to change the setting.

If you have checked all of the items listed above, but there is still no improvement, please contact the nearest Canon Service Center.

If you are experiencing trouble with a lens made by another manufacturer, you should contact manufacturer of that lens instead.