had this problem with my 1d mark iin and 5d, the ff procedures pretty much fixed the problem:
1. Remove the lens and replace the body cap
2. Put the camera in manual cleaning mode with the body cap in place. You might be able to do this with the lens on, but I have always removed it and I don't argue with success.
3. Leave the camera in manual cleaning mode for maybe a minute or so.
4. Check to see if the hot pixel is gone.
5. If not, repeat the procedure once or twice more.