T2i will not turn on

[jhowell]

I've taken all the steps outlined in the troubleshooting section of the user manual, but the camera will still not turn on. I have replaced the battery with a new Canon battery, but nothin will happen.

Suggestions?

[RobertTheFat]

Did you charge the new battery? They aren't always delivered fully charged. When did the camera last work correctly? How has it been stored since? Was it ever dropped or gotten wet? Etc., etc.

One plausible place to start looking is the battery door. The door operates a very small switch that tells the camera that it's closed. That switch can get stuck or broken, and the camera won't turn on if it thinks the door is open.

[TCampbell]

There is a micro-swtich on the battery door and another on the memory card door.  If either of those doors are not completely closed so that the tab engages the button then the camera will not power on.  

I've not done this myself, but others have reported that if the memory card isn't correctly formated then the camera wont power up.  

If you own more than one camera, do not swap the memory card between cameras unless the card is reformated.