EOS R Won't Function with EF 70-200mm f2.8 L Attached

[Compactvic]

I have an EOS R, with a Canon EF to RF adapter. I have been using this setup with a Canon EF 24-70mm f2.8 L USM lens for a year with no issues. Today I got a Canon EF 70-200mm f2.8 L lens. When attached to the camera and adapter, the camera will not turn on. The top screen is on but the camera will not function. When I remove the 70-200 lens, attach the 24-70 lens, and open and close the battery case, the camera will work. 

What am I doing wrong? Is this lens not compatible? Did I purchase a bad lens?

[deebatman316 · Accepted solution]

Will the lens work on a Canon EF or EF-S Mount camera. If it doesn't you have a bad lens. If it works correctly on an EF or EF-S Mount camera the mount adapter could be faulty. The lens is compatible via the EF-RF Mount adapter. Does this lens have IS or is this a non-IS lens. Is the mount adapter Canon or a 3rd Party. Also which version of the mount adapter if its a Canon Mount adapter. The basic one, Control Ring or the one that filters can be installed in. Also DO NOT change lenses with the camera on make sure its OFF. Also DO NOT open the battery or memory card door with the camera ON.

-Demetrius

Current Gear: EOS 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 50 F/1.8 STM, EF 85mm F/1.8 USM, EF 70-200mm F/2.8L IS III USM, 430EX III-RT, 470EX-AI & 600EX II-RT

Retired Gear: EOS 40D, Sigma 17-50mm F/2.8 EX DC OS HSM & EF 28-135mm F/3.5-5.6 IS USM

[Compactvic]

Unfortunately I don’t have an EF Mount camera to check the lens. The adapter is the basic Canon adapter without the control ring. The lens does not have IS. 

[deebatman316]

If the lens is shutting down the camera. The lens is faulty. A lens communication error won't shutdown your camera. I would return the lens.

-Demetrius

Current Gear: EOS 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 50 F/1.8 STM, EF 85mm F/1.8 USM, EF 70-200mm F/2.8L IS III USM, 430EX III-RT, 470EX-AI & 600EX II-RT

Retired Gear: EOS 40D, Sigma 17-50mm F/2.8 EX DC OS HSM & EF 28-135mm F/3.5-5.6 IS USM

[major321]

Hello

Clean the lens contacts* to restore connection with the body. b) Try using a different memory card. All memory cards should be properly formatted in your camera prior to use. *Warning - Do not clean lens contacts on either a Canon lens or the camera body with an eraser! May be it will work for you.

[shadowsports]

@Compactvic

Greetings. Where was this lens purchased from?

Is it possible to take it to the retailer so it can be tested?  

[Waddizzle]

It sounds like a bad lens.  I would rule out repairs and pursue getting a full refund.

[shadowsports]

Yes.  Exactly the direction I was heading in.  Too many coincidences for a new lens.