I see no service manual on the web so back to Canon to see if they can fix it.
As to the power source, did you try the standard Canon battery? Sadly it sounds like a dead camera.
I've acquired a Canon Rebel t3i that has been previously modified by a computer tech for his live streaming website. I live in a town of tourism, on a property that is considered premiere advertising real estate and a few years ago this guy approached me wanting to install his system on the house. I let him do so and even paid for the electricity free of charge. But the website has since been down for like 2 years and I haven't heard from him so i figured I would just sorta help myself to the equipment. Anyway, there is so much tech going on here it looks like a foreign language to me. I only want to use the camera which I removed from the waterproof housing he mounted it in. But I can't seem to turn it on because of the modifications he made and I'm not exactly technically savvy so I need help. First of all, he attached the battery system to a permanent energy supply (my wall outlet) which is fairly simple for myself to figure out. But he also drilled a small hole in the camera (next to the power button and dial used to switch between settings) with 2 small wires attached to something inside the camera. I assume this was so he could personally turn the camera on and off from his computer. These wires, including the power supply, were connected to another waterproof console that he constructed with all sorts of gadgets including apple tv and **** i don't understand. The whole system looks like the interior of a spacecraft as far as I'm concerned. Anyway, like I said I just want to get the camera to function by itself so I can take some shots but it wont turn on when I just plug it in with the power source. Anybody who is familiar with this kinf of stuff have any suggestions?

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