It would seem that the camera is having issues completing its Power On Self Test or POST. In this particular camera this can be caused by two main issues.
* '''Mainboard Failure''' - The camera has physical damage internally that is preventing the mainboard from competing its power on sequence and presenting you with an error code. (Bad - only canon can fix this)
* '''Corrupted Firmware''' - The software that runs the camera is corrupted preventing the camera from properly starting. (There is hope - read on!)
I have had success with reloading the firmware on my old camera when this same error happened after I left my camera in my minivan on a sweltering day. Follow the link below for the latest firmware and instructions on how to reload it.
[http://web.canon.jp/imaging/eosd/firm-e/eosdigital5/firmware.html|http://web.canon.jp/imaging/eosd/firm-e/eosdigital5/firmware.html]