Map out dead pixels on Canon EOS 5D
Here is a non-official way (do-it-yourself-at-home) on the forum to map out dead pixels on Canon EOS 5D.
Make a shot with lens cap on at eg. 1/5 seconds and 1600 ISO with auto-focus off (or turn off noise reduction in CF and make shutter open for longer). After that go to Sensor Cleaning and turn it on (as cleaning the CMOS when mirror is up and shutter is open, but leave lens on) for a minute. Yes, it should be long enough. After that, switch camera off, then - on and - YOUR DEAD PIXELS ARE GONE!
Have you tried that?