topic EOS 5D Mark IV won’t allow me to change aperture in EOS DSLR & Mirrorless Cameras

EOS 5D Mark IV won’t allow me to change aperture

CanonShooterDev — Tue, 01 Apr 2025 05:24:31 GMT

Recently bought a used EOS 5D Mark IV off of the market & shortly noticed that it wouldn’t allow me to change the aperture (F16 was the only option shown). At first I thought it was a faulty lense, until i tried a brand new EF Canon lense and same thing occurred except this time it’s stuck on F22. I updated firmware, and reset all settings to default and nothing has worked for me so far. Starting to think it’s a problem with the Body itself. Any tips on what the issue is, and how to fix it?? How much in repairs am I looking at if needed??

Re: EOS 5D Mark IV won’t allow me to change aperture

Waddizzle — Tue, 01 Apr 2025 06:28:59 GMT

If you purchased a used camera, it is advisable to go through the entire menu system and reset everything you encounter with a reset option. You want to begin using the camera with the camera settings in a known state. This might take ten minutes to complete.

Re: EOS 5D Mark IV won’t allow me to change aperture

MikeSowsun — Tue, 01 Apr 2025 13:23:39 GMT

When this problem comes up, it is usually because the user has Multi Function Lock engaged.

Re: EOS 5D Mark IV won’t allow me to change aperture

CanonShooterDev — Tue, 01 Apr 2025 13:24:58 GMT

I went through and reset everything also, same results, an aperture of F22 was the only option available after reset as well

Re: EOS 5D Mark IV won’t allow me to change aperture

MikeSowsun — Tue, 01 Apr 2025 13:47:09 GMT

Did you check to see if the Multi Function Lock is off?

Is the aperture stuck in all modes? Program, Aperture Priority, Tv Priority, Manual mode, etc?

When you operate the Depth Of Field button, does the aperture stop down to f/22?

Re: EOS 5D Mark IV won’t allow me to change aperture

CanonShooterDev — Tue, 01 Apr 2025 14:01:54 GMT

So I tried this also last night, it wasn’t the multi lock function either, only allowed me to be on an aperture of F22, every other function seems to work just fine

Re: EOS 5D Mark IV won’t allow me to change aperture

deebatman316 — Wed, 02 Apr 2025 00:07:39 GMT

Are you using any 3rd Party accessories attached to the camera if so remove them. There is a Custom Function on the camera to restrict the lens' aperture range. Did you reset the Custom Functions too. Resetting the camera to factory default DOES NOT clear Custom Functions. What lens are you using please provide the FULL NAME of the lenses in question. What aperture is set with the camera in Full Auto (A+ Mode). I have posted example lenses below to help identify your lens.

Re: EOS 5D Mark IV won’t allow me to change aperture

Waddizzle — Wed, 02 Apr 2025 01:24:55 GMT

What lens are you using? What shooting mode are you using?

Have you tried a different lens? Do you have the same issues with Green Automatic shooting mode?