Try a hard reset:Remove the batteryRemove the memory cardRemove the lensSwitch the camera on for a 30 minutesSwitch camera offBut battery back inTurn camera onSet the mode dial to M (Manual)
Go to the Setup menu and clear all camera settingsTake a shot with out lensIf mirror flips up and back and a clear frame is displayed, put lens on and take shot
If unsuccessful, try the procedure once more. If normal operation is not restored, the camera will require professional service.
You can contact Canon at the link below:
OR The third party service at the following link
Please keep in mind that my diagnosis & solutions provided are directly dependent on the accuracy of your description of the problem. As with any "do it yourself" fixes, success is a "team effort", since I can't see or touch the camera, and relies on the customer's manual dexterity and ability to follow the instructions well. If the "do it yourself" approach doesn't work out for you and you need conventional repair, please let me know.
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