Canon 50D - Not Powering On

[Joiemagic]

I just posted about an issue with my 1D Mark IV, so I pulled out my 50D backup camera, which I have not used for at least 5 years.  It has been sitting in a camera bag the entire time.  When I charged up the batteries which were totally drained and tried to turn on the camera, I get nothing.  There does not seem to be any power to the camera.  I ordered new batteries and charged them up, but got the same results.  Absolutely nothing, no power to the camera.  I tried taking the battery grip off and using a single battery in, but have the same results.

Any suggestions, please help.  I have a number of upcoming shoots in the next few weeks.

[Joiemagic]

All I can say is the camera is working.  I can take photos again with my 50D until I get the rear screen replaced on my 1D.  So, I am a happy camper...  Being I did nothing else, what appeared to fix the issue was changing the CR2016 battery as was suggested.   

[normadel]

I have a 30D that DOES power up without the CR2016 in place. 

Maybe some Canon person familiar with these things can explain this.

[deebatman316]

Maybe its specific to the EOS 40D I can't really explain it.

[nobodyeasy]

Just like the CMOS battery on a motherboard dies, the computer will lose its BIOS settings, including the date and time, when it's powered off. This can cause boot issues and incorrect hardware configurations.