80D won't power on -- suddenly bricked

[serrels]

I bought a refurbished 80D from Canon about two years ago after my trusty 70D had a main board failure. The 80D has worked flawlessly since. Used it last weekend, no problems. Today, it won't power on. When I went to use it, I noticed the power switch was set to "On" and the Live View / Video toggle was set to "video". I suspect a pair of toddlers got their fingers on it while it was on my desk. I typically have auto power off set to 5 minutes and I can't remember if that shuts the camera down in video idle mode or not. But it's also possible that it sat in video idle until the battery drained to zero.

I checked all the usual causes. Doors all closed, tried different fully charged batteries (all Canon), different cards, different lenses, no lenses or cards, etc. I tried Canon's procedure to completely shut down the camera but it did not help. I get no LED flash when I insert a freshly charged Canon battery.

Any ideas? I don't see much mention of 80D failures on the web.

Thanks in advance

[RobertTheFat]

If toddlers indeed got their fingers on it, is it possible that they dropped it? Cameras don't like to be dropped.

[Waddizzle]

"I checked all the usual causes. Doors all closed, tried different fully charged batteries (all Canon), different cards, different lenses, no lenses or cards, etc. I tried Canon's procedure to completely shut down the camera but it did not help. I get no LED flash when I insert a freshly charged Canon battery."

That does not sound good.  Try that stuff with the memory cards removed.  

BTW, what was the "Canon procedure" you tried?  The only unofficial "procedure" that I am familiar with says to remove all the battery, memory cards, and any accessories like a battery grip.  Once that is done, then turn on the power switch, press and hold the shutter button for at least 10 seconds.  

Turn off the power switch.  Insert a fully charged battery,  Do not insert a memory card, yet.  Turn on the power switch.  Hopefully, the camera should be fully reset back to the point that even the time and date has cleared.

[serrels · Accepted solution]

Got it working again. Took a while to figure out what was going on so I'll share in case anyone else has this problem.

Turns out that even though the card door was closed, the tab on the door that is supposed to engage the door switch was sliding past the side of the switch. I noticed that there was a rub mark on the tab, indicated by the arrow in the photo, and wondered if the tab was getting wedged between the switch and body. I now have to make sure the door is firmly pressed against the body before sliding it closed.

Here's the switch:

I wonder something inside has shifted or come loose. I blame the toddlers.

And, Waddizzle, it sounds like what I thought was the Canon procedure is actually the unofficial procedure that you described.

[Alby47]

Same issue, but solved. The memory card door doesn't seem to close firmly hence, the power off troubleshoot. Guess it has to do with water resistance policy embedded in the camera. Cheers.

[ebiggs1]

A tiny drop of a lube perhaps WD40 should help.  I did say "tiny".  Some is good more is not.

[serrels]

It was about 10 months ago when I first posted about this problem. By making sure I was closing the door correctly, I was able to avoid any issues for about a month. It started happening again and it didn't matter how carefully I closed the door. Turns out the switch and tab would slip by each other while using the camera, instantly powering it down. I ended up taking the back off and shimming the switch so it made better contact with the tab. And that worked until just a couple weeks ago. So, I took the back off again and, this time, I taped down the switch so the camera thinks the door is always closed. No problems since. I just need to be careful that the camera is off before removing the card.

Also, I always recommend using DeoxIT as a lubricant on any mechanical electronics (switches, potentiometers, contacts, etc) instead of WD40, which acts more like a solvent than a lubricant. And if you need a "dry" lubricant that won't collect dust and blocks out moisture, use silicone spray.

[ebiggs1]

Everybody has their preference but I have used WD40 on electronic devices since it was invented. It was designed for electronics.