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EOS 40D Won't Power Up

robinkaspar
Apprentice

I have a 40D I haven't used since I bought a 70D when it came out. The 40D has been stored in my bag in a closet without a battery, CF card, lens (body cap only), without anything that could render it useless. I brought it out of storage (not a hot attic, etc) in preparation to donate it to a worthy cause. It won't power up with the original Canon batteries (fully charged according to the original Canon charger). I bought 3rd party batteries which won't power it up. I bought a charger for those batteries and still the camera won't turn on. I can't think what else to try. My plan was to format all the CF cards I have and donate them along with the camera. It looks perfectly normal, the battery contacts look clean. What do I do with it? I don't want to invest any more money in it. 

1 ACCEPTED SOLUTION

Anonymous
Not applicable

Your camera has a date/time battery besides the camera battery. You could try replacing that battery. Your camera manual has the instructions on how to replace the date/time battery.

Screenshot 2023-07-28 091504.jpg

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9 REPLIES 9

Anonymous
Not applicable

Your camera has a date/time battery besides the camera battery. You could try replacing that battery. Your camera manual has the instructions on how to replace the date/time battery.

Screenshot 2023-07-28 091504.jpg

Well, duh! Forgot all about this battery and no one else I've asked has mentioned it. Thanks so much Bob, I'm back in business.

Anonymous
Not applicable

Great to hear!

This makes no sense. Are you saying you just replaced the Date/Time battery and your camera now suddenly works? I also have a 40D and it functions very well with the Date/Time battery entirely removed from the camera. 

There must be some other reason why your camera would not turn on. 

Mike Sowsun

I wish I knew. But I replaced the date/time battery and inserted the other battery, fully charged, and the camera then powered up. So, it was the date/time by itself but the combination of the two. (I guess.)

*wasn't"

Anonymous
Not applicable

I've heard of others having the date/time battery cause this issue on other Canon cameras.

normadel
Authority
Authority

This could be a case of a temperamental On/Off switch. On a (15-year) old camera, switch contacts can become corroded, even if it's just a light film on them. Repeatedly turning the camera on & off can wipe the film contacts clean. 

An application of an electronics contact cleaner may keep it working for another 15 years.

shadowsports
Legend
Legend

My guess.  The switch on the battery door might have been the cause.  🤔

~Rick
Bay Area - CA


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