01-02-2013 03:50 PM
I have a 7D about 3 years old now. One battery is original , the other is 6 or 7 months old.
I upgraded to the latest firmware version 2.0 shortly there after (Don't know if there is a relationship?) one battery could not communicate, the other worked fine. I recharged it and it worked one time more then errors after that. the second battery worked for about 3 more days then it failed to communicate as well.
1. Batteries ?
2. Charger issue causing chip in battery to go bad?
3. Camera battery sensor chip gone bad ?