Canon 70-200m F2.8LUSM (MK1) autofocus not working

[Cj7509]

I recently purchased a 70-200mm F2.8L USM lens and when I hold the shutter button half way, the lens is just focusing back and forth, and not finding anything to focus on. If it does focus on an image,80% of the time the image is out of focus. I’ve tried it on a T5 and an 80D but the problem still exists. Manual focus works great and the pictures look good but the AF is basically focus hunting.I’ve attached videos/pics in the links. Could also be user error 🤦‍♂️. Thanks I’m advance for your help.

https://imgur.com/a/jy0Wwhu

[jrhoffman75]

Looks like your lens is severely damaged.

[Cj7509]

Yes, I know that the collar is missing. The seller had mentioned that it was missing but didn’t mention that the first group lens was missing so I had to purchase/install one since canon can’t service the lens.

[jrhoffman75]

I suspect you have a Canon EF desk ornament/paperweight. Can't even call it an EF-L paperweight since it doesn't have the red L ring.

It also looks like the area behind the element is damaged.

[ebiggs1]

Unfortunately replacing parts is only part of the work required to repair an AF lens.

[shadowsports]

@cj7509,

Sorry sir, but you bought a lemon. The "bargain" is no longer a good deal. "Seller didn’t mention that the first group lens was missing" Red Flag.

You can try sending it to MidWest Camera dot com and hope it's not a money pit.