The Sleeping Giant's Sea Lion

by Jakub

submit your photo

Hall of Fame
View past winners from this year

Please participate in Meta
and help us grow.

Take the 2-minute tour ×
Photography Stack Exchange is a question and answer site for professional, enthusiast and amateur photographers. It's 100% free, no registration required.

If I see the "cannot communicate with battery" error message on a Canon 7D, is there any way to fix it without sending it back to Canon?

share|improve this question
Are you using an OEM battery from Canon or a third party battery? –  dpollitt Oct 4 '11 at 16:03
Hmmm..good question. This is actually not my question - it's a problem brought to my attention by Twitter (friend of a friend situation). I think your answer gives a lot of useful suggestions, though. Thanks! –  Laura Oct 4 '11 at 17:32
I've been tryng all the possible solutions, but any solve the situation. A couple of days ago I was working in a very wet enviroment, so I guess it is a matter of humidity. I will leave it with all its doors opened and will wait. Anyway, it permits me to use it although has no communication with the battery –  user6884 Oct 10 '11 at 21:08

3 Answers 3

up vote 3 down vote accepted

A few things to try:

  • Try a second battery
  • Try a second body
  • Try OEM and third party batteries
  • Accept the warning message about the lack of communication and try to use the battery anyways
  • Try pulling the battery out and reseating it at least a few times
  • Try removing the tiny watch style battery as well as removing the regular battery at the same time. This will reset some if not all things on the camera, so keep that in mind.
  • Update your firmware to the newest version
  • Try a battery grip if you have one
share|improve this answer
Swapping to another battery, powering up and back down, then putting the first battery back in has worked for me the very few times I have seen this error. –  Michael Clark Feb 17 '13 at 23:53

I saw a post that suggested putting the camera body in the freezer for 6 minutes. Tried it, didn't work. Yesterday I thought I would try it again for a little longer. I put the camera body in the freezer at 10 am. At 6 pm. While working the discus event with my secretary, she said "hey you know there is a camera in the freezer?" Panic. It was frosty. Removed the battery, let it defrost for over an hour, put in charged battery, it worked, no more battery issue. Bizarre.

share|improve this answer

I also has problem with "battery communicate". As some user in internet I doesn't find one screw on bottom of body.

enter image description here

After a while I found it near the motor. He was dragged a magnet and short T-line on the battery housing.

screw in the center of photo

This photos of another user with some problem about screws (he miss 2 screws):

enter image description here enter image description here

Short circuit by screw!!! SOLVED: Canon 7D “will not communicate with battery”

share|improve this answer
Can you elaborate a bit more? Is this likely to be the case or just one possible cause? –  mattdm Sep 9 at 12:30
OK. This is the most possible cause of error "will not communicate with battery" –  Ilya Maslov Sep 11 at 4:48

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.