I have a strange issue with my 5D3. With no ML the camera appears to work perfectly. As soon as I load ML 2.3 I get Err 06 - Self cleaning sensor unit malfunction.
Has anyone else come across this issue?
Can you start the camera with ML by holding the SET button at startup? (so you should see ml-off in the firmware version)
Does it help if you don't load any modules? (delete the modules and settings directories)
Edit: sorry unrelated post