Showing results for 
Search instead for 
Did you mean: 

EOS R5 Err 70


I just received a new EOS R5 and out of the box I was getting an err 70 lockup. I thought updating the firmware would resolve the problem but the err 70 continues. I have now received a message 20 or 25 times over the course of 100 frames. Is the a comen problem?




This is not common.

Is your battery fully charged?

Start by performing a factory reset of the camera.

What type of memory card(s) are you using and were they formatted in the camera?

What type of lens are you using on the camera?


Bay Area - CA
~6D2(v1.1.1) ~Many Lenses ~DxO PhotoLab Elite ~Windows10 Pro ~EVGA RTX 3080Ti FTW3 Ultra ~ImageClass MF644Cdw ~Pixel6 ~R5C On Order

Good morning, the battery is fully charged, I am using a SanDisk Extreme PRO CFexpress Type B and it is formatted. I am using a EF lenses with the Canon EF-EOS R mount adapter. Canon EF 24-70mm f/2.8 L USM, Canon EF 17-35mm f/2.8 L USM, and Canon EF 70-200mm f/2.8 L USM. I will attempt to reset.


The problem is with the Canon EF to R Mount Adapter.  I shoot timelapes and get ERR 70's all the time when I'm using an EF lens on that adapter. The problem seems to occur when the camera needs to control the aperture.  When I set my aperture to it's largest setting - in your case F/2.8, I never get the ERR 70.   But if I set it to any other aperture (3.5,4, 5.6, etc) I will eventually get an ERR 70 at some point during my timelapse - unless of course I stop my timelapse before it occurs.  It usually takes 150+ frames before it shows up.  I've tested this with Canon and 3rd party lenses. I've also tested this with a variety of SDXC and CF Express Type B memory cards, and with different batteries.  You seem to be getting the ERR 70 much more often than even I was getting them. 
I just purchased the Canon 24-105 F/4.1 - F/7 lens and no lockups even after 1000 frames of a timelapse.  I also just purchased a Rokinon 14mm AF RF Mount lens and again no ERR 70 lock ups.  There is some communication issue with their adapter and EF lenses.  I've reported my findings to Canon and despite that all they did was replace my main PCB board (twice) and it didn't solve the issue.   So for me it's not the battery, it's not the memory card, it's not the main PCB, it's not the battery remaining - its the EF lens with their adapter.  

Now I have read reports of people getting lock ups even with RF lenses but this seem to have something to do with back Autofocus which I believe firmware 1.5.1 was supposed to correct(?), but I have not yet had this issue at all and I shoot a LOT of frames.  However, most of what I shoot is with manual focus (for timelapse).



I Googled “EOS R5 Error 70” and got a lot of hits. Most of the reports seem to point to a defective main circuit board or motherboard. I would return the camera to the seller for an exchange or refund, or send it to Canon for warranty service. 

Mike Sowsun
80D, 5D Mk III


The problem is not restricted the EF to R mount adapter. I took delivery of a EOS R5 4 days ago. I have used only two new R mount lenses (RF 24 - 70mm f/2.8 and RF 85mm f/2 Macro IS STM). On each of the last four days I get the dreaded Err 70 error message over half a dozen times every day. Yes, turning off the camera and removing/reinserting the battery resolves the problem, but it happens consistently with both lenses. I am returning/exchanging the camera at B&H. I have never experienced anything like this with many years of experience with Olympus, Sony & Leica. This is my first Canon. I was so excited and greatly disappointed with what seems to be a problem experienced by many Canon users on a variety of Canon cameras. What gives??? How widespread is this problem? What does Canon have to say about the cause and the fix???

I know that it’s possible to get an Error 70 for  reasons other than what I am stating.  Error 70 is a communication error and normally has to do with memory card writing issue or lens communications.  But in my case I had two main PCB’s replaced and both times the error would still show up at some point in every timelapse (when not shooting wide open).   Since I have been shooting with RF lenses I have shot thousand of frames and at least a dozen timelapses and have not had a problem since.   So for me the adapters and my EF lenses were causing a communication issue when the camera had to control the aperture of the lens.  For those that don’t shoot timelpase it might only show up once or twice in a year - but for me it would show up everyone I shot a timelapse (but not usually until after 170 or 189 frames.  

Insight32 - thanks for your response and sharing your experience. I just don't understand why Canon, as far as I can see from searching the web, has no official statement/response/solution/fix to what seems to be a pretty prevalent problem. This simply should not happen on a flagship camera (or any camera made by Canon) fresh out of the box. Can you imagine purchasing a brand new Mercedes Benz S580 and 2 days after  you drive it out of the showroom you get an error message on the dashboard that says - "Error 70 - car unable to operate. Try turning the car off and restarting the engine" - and Mercedes remained quiet and pretended that there was not a problem??? If there all of these threads all over the web regarding the "Error 70" problem - where is the official response from Canon on what is obviously a serious and recurring problem???

I don’t disagree.    I’ve been a Canon user for over 25 years and have never had any problems with their cameras, so it surprised me as well.    Err 70 has been around for years in virtually all models, but has never been an issue I’ve ever come across.  You can google “Err 70” and find articles from the cameras in 2008, and so on.  You can also google “Sony camera error” and find a ton of posts as well.    The only thing that surprised me about this error 70 is that it affected me and that Canon, like you mentioned, doesn’t seem to addressing it - privately or publicly.