My Canon 70D was working great until I started using it for video.
At first the camera would freeze after awhile and I could fix it by turning on/off or taking the battery out.
I thought it might be a bad sd card so I got a new one and things were working again for regular photography.
Had to do some more video and the camera froze, this time for good. Last thing it said was Error 80 and I haven't been able to turn it on since. Not even the red power led flicker. Genuine Canon battery fully charged. I searched the internet and it didn't take long to find other 70d owners with similar complaints. This camera only about 2 years old and I am the sole owner. This really sucks.
Based on what I've read, your body has suffered a failed mainboard assembly. No recovery, only option is replacement. Repairs seem to avg. $285-$400 but I have no experience with this. The forum does have a few threads from others who have the same failure. You've probably found them. Given the number of reported failures, I'm suprised its not been acknowledged and recitifed. But it seems the burden has fallen on the consumer. Sorry to hear about it.
Bay Area - CA
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If Canon Canada charges you $300 for both part and labor, it is not a bad deal. The cost of the PCB mainboard itself sold online exceeds that amount of money and there is no guarantee that you can replace it yourself.
Good luck with your repair and it's time to consider buying a separate camera for video purpose.
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