Corrupt SD Slot? Canon 5D MK3 won't turn on.

[lblum]

I've had a strange issue happen several times in the past two months. My Canon 5D MK3 isn't even 2 years old at this point, and I'm the only owner.

Suddenly one morning before a wedding - my 5D MKIII would not turn on. After removing the batteries, including the clock battery, and waiting a while, I was able to reset the camera. After various tests, I've narrowed this issue down to introducing the SD card.

It doesn't matter if I have zero cards in my camera or a CF card already inserted - when I insert any SD card I have (I only use Sandisk Pro Extreme cards), my 5D will shut off and won't turn back on. I can insert the same SD card into my Canon 6D and I'll have no issues. Sometimes rather than shutting off, it will allow me to access the Quick Screen and menus, but will not fire.

Has anyone ever experienced something like this?

[diverhank]

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@lblum wrote:

It doesn't matter if I have zero cards in my camera or a CF card already inserted - when I insert any SD card I have (I only use Sandisk Pro Extreme cards), my 5D will shut off and won't turn back on. I can insert the same SD card into my Canon 6D and I'll have no issues. Sometimes rather than shutting off, it will allow me to access the Quick Screen and menus, but will not fire.

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Very strange problem indeed.  The only thing I can think of is that there is some foreign metallic object that had fallen into SD card slot and upon inserting the card would make contact with the pins and short them out.  I would shine a light and inspect that area carefully.

On the other hand, there is no real reason to use the SD card slot...I'd just leave it empty all the time :).

[lblum]

I hadn't thought of that! I'll definitely take a peek inside.

Honestly, I only like to shoot dual cards for the idea of safety during weddings (recording in two places). Other than that there isn't a point...it only slows down my write speed!

[diverhank]

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@lblum wrote:

I hadn't thought of that! I'll definitely take a peek inside.

Honestly, I only like to shoot dual cards for the idea of safety during weddings (recording in two places). Other than that there isn't a point...it only slows down my write speed!

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Please do let me know what you found after checking...

Regarding the dual use - I understand what you're saying but while I don't shoot professionally, after nearly 100,000 shots out of my 5D3, I have yet lost a single picture due to failure of cards or card slots.

Also, your backup 6D does not have the extra slot, anyhow :).  Plenty of pros are using that for weddings...

[gacemite]

My 5d mark iii any time memory card is inserted into the camera, the power will off, the camera only power on without memory card please how did you solve ur issue

[lblum]

I never did find a true solution to my problem. I was able to fix it by removing the batteries from the camera and also removing the clock battery, but you'll need a special tool in order to remove it. I used a tool that's used to repair eyeglasses. After fully resetting the camera, the problem went away. It happened maybe one more time after this, and hasn't happened since.

[gacemite]

Thanks so much, now my camera is working fine with cf card, but anytime I put SD card the camera will not on again

[Annmarie610]

Hi! I just came across this. The same thing happened to me today with TWO different mark iii cameras. Just before a wedding. I usually shoot weddings on two cards but had to only shoot on CF because it would power down. I was panicking for a solid 2 hours. What did you end up doing?

[lblum]

Hi! See my comment above. The only thing I could do was an entire shut down of my camera, which required I remove all batteries, including the clock battery. I hope that solves your problem! I've since upgraded to the MK4.

[Annmarie610]

Thanks! It eventually came back on on its own, but I am now so scared it will happen again at a wedding. I think I got a few gray hairs yesterday in a matter of 2 minutes. Lol.

[Waddizzle]

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@Annmarie610 wrote:
Thanks! It eventually came back on on its own, but I am now so scared it will happen again at a wedding. I think I got a few gray hairs yesterday in a matter of 2 minutes. Lol.

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Haven’t you tried any of the suggested remedies.  Reset the camera back to factory defaults.  Reformat any SD cards that you use.

Remove any lens, memory cads, and  the main battery.  Turn the camera switch ON.  Fully press and hold the shutter button for at least 10 seconds.  Turn the camera switch OFF.  These last steps should also reset the time and date, and completely reset everything in the camera.

Try to use a fresh memory card, or one that has been freshly reformatted by a camera.  SD cards should always be reformatted prior to first use in the camera.  Only use full size SD cards, too.  Avoid the micro-SD cards with adapters.