AF (Autofocus) does not operate (EOS M3)

Article ID: ART162345 | Date published: 09/17/2015 | Date last updated: 09/17/2015


AF (Autofocus) does not operate (EOS M3)


Check the lens' focus mode

If the lens' focus mode is set to [MF], auto focus will not operate.
In the menu, set [Focus mode] to [AF], or set the focus mode switch on the lens to [AF].

  • [Focus mode] will be displayed when an EF-M lens is attached. It will not be displayed when an EF or EF-S lens is attached.
  • With [ ], [ ], or [ ] this setting will not be displayed. (It will be set to AF automatically.)

  • With an EF-M lens

1. Set the cameras power to [ON].

2. Press the [ ] button.

3. The [MF] icon is no longer displayed.

  • With a non-EF-M lens
Set the lens focus mode switch to [AF].

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 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.
Precautions on cleaning contacts:
  • Do not wipe the contacts with a wet cloth. It could cause malfunctions.
  • Do not touch the contacts directly with your hands. Touching them with your hands could cause corrosion, which would cause the camera to become inoperable.
  • When cleaning the contacts on the lens side, be careful not to damage the lens surface.
  • If the contacts are particularly dirty, please contact the nearest Canon Service Center.

Securely mounting the lens

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.
Please mount the lens securely, as shown in the image below.

If using an EF or EF-S lenses, attach the Mount Adapter EF-EOS M securely.

Check the [C.Fn III: Others-Custom Controls-Function Assignment Shutter/AE lock] Custom Function Setting

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

In this case, by pressing the shutter button halfway, the camera start to meter.

In cases like these, change the value to [AF/AE lock].
Please see the Instruction Manual 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.
Note that, if you are experiencing trouble with a lens made by another manufacturer, you should contact manufacturer of that lens instead.



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