Cannot communicate with battery - 7D

[aridillse]

Dear Friends,

I am a proud owner of 7D for the past 2.5 yrs and have done many trips and shooting with that.

I am not using any battery grip. Have 2 Canon original battery with me.

Fromyesterday night I am getting an error  "Cannot communicate with battery". It is same described in the below link also :-

http://kbsupport.cusa.canon.com/system/selfservice.controller?CONFIGURATION=1011&PARTITION_ID=1&secu...

I am using Original Canon battery and I have tried with both of them but no result.

As per User Guide ,

"

If the message "Cannot communicate with battery" is displayed when checking the battery status, select [OK] and continue shooting. Please note that the battery level indicator will appear blank.

"

My concern is :-

1. If I ignore that and continue shooting , will it create any problem to the Camera functionality ?

2. Wil the battery drain fast due to that ?

I am Ok with not displaying the battery infor as of now ( which I will repair by Canon) but need to confirm that the battery functionality will remain as usual. I will be travelling for a birding trip soon and I due to short time I dont want to send it to repair...

Please guide.

Warm Regards,

Ari...

[olivierit]

John & Jim,

I followed your video instructions, although it was a bit difficult without the plastic blade you'd had, I used a fine tip flathead screwdriver to gently & gingerly remove the cap....found the screw deeper down than where yours was, and fortunately, my screwdriver was slightly magnetized and was able to retrieve the screw.  I put it all back together, and was VERY pleased.

THANK YOU SO MUCH!!!

Next camera will be a NIKON.

[emptech]

As I said, the most difficult time I had was in removing and replacing the plastic floor plate, John in his video used a plastic knife, tends to cause less scratching, gouging, I used a small screwdriver.  Although I didn't scratch or damage the plastic, I'll remember to keep a disposable knife handy for that purpose.

Thank John in Cozumel for his video.

Jim

[Zathrum]

I was so hopeful when I saw this.   I had realised there was something rattling around inside my camera when both of my batteries stopped being recognised.

Followed the instructions, found and returned the loose screw to its rightful home....

(that bottom plate is tricky to get back on the camera !)

But no luck, same response from both batteries.

I will be examining the board (etc) again one evening and I might try a battery in or from another camera...

Keep trying.....

[emptech]

---

@Zathrum wrote:

I was so hopeful when I saw this.   I had realised there was something rattling around inside my camera when both of my batteries stopped being recognised.

Followed the instructions, found and returned the loose screw to its rightful home....

(that bottom plate is tricky to get back on the camera !)

But no luck, same response from both batteries.

I will be examining the board (etc) again one evening and I might try a battery in or from another camera...

Keep trying.....

---

Unfortunately, since you heard the screw bouncing around inside, it may have shorted between some traces and may have caused attitional damage.  I'm assuming that you completely rebooted the camera, removed the main battery and the coin cell.  When you did that, you had to reset the time, etc, as it would bring the camera back to factory defaults.

Canon is very good at selling repair parts, if you don't know the part numbers, they are very helpful.  I don't have a diagram of the camera but believe the bottom board is the power supply board.  I'd hate to see you buy circuit boards until the problem is solved.  I was unable to find a service manual on the camera but did find a parts manual, don't have a link for it at the moment.

Good luck with it -  Jim

[squiggly]

This is a really useful thread, thanks for all the advice about taking apart the camera.

How will I know (or how can I test) if the loose screws have done any damage?

I've retrieved 2 loose screws (on the left as seen in the video, but also the one on the right) and I've still got a permanent "Error 40" message showing, despite the screws being back where they should be. The left one was very close to where it should have been, the right one I had to go a little deeper, and found it magnetically stuck to the cylindrical metal thing on that side.

Any help greatly appreciated!

Thanks,

Tom Quigley

[methom]

I had the battery communication error and tried the fix in the video. The screw on the left side (orientation per video) was very loose, but still in place. I put it all back together and still had the issue. 

Based on squiggly's comments, I took apart the camera again to find the 2nd screw (on the right side) loose in the body and 'magnetically stuck' as squiggly describes. I got the screw out and put it in the right-side hole, reassembled the bottom, reinstalled the battery. And this worked - no battery error. 

I never had the Error 40 but the comments about two screws out of position was helpful. 

[Zathrum]

Had another fiddle with it. Popped the button cell out and re-seated the screw. It worked ! For all of one attempt....
It did allow me to see that the battery I was using was very low in recharge-ability. Another successful attempt showed me that my other battery was in great shape.
Have ordered a new cr1616. I'm wondering if it uses that battery to power the battery condition circuit and maybe that is worn out....?
Will see....

It's just odd behaviour.....

[Snowlan]

A new developement to this issue I've lived with for 1.5 years by taking the battery out every time I'm done with it so it doesn't drain over night.  A little background: I bought the 7D used with two batteries included that looked to be original Canon, and everything worked as it should 2011-2012.  Right before a vacation I forgot one of the batteries and the charger on the ship I work on, and replaced them with  new Canon products.  I noticed the battery looked very similar to the ones I had, but included a silver stamp area on the back with the year/month stamped into it (not pressent on the first two).  As soon as I used this new battery (and if I rememeber correctly a firmware update) I lost communication with all 3 batteries.  It was frustrating but couldn't bring myself to spend the $300+.

Strange thing happened today, I just bought a 7DII and while charging the included battery I popped in one of my old ones to play with settings - same error message!  I took out the battery and it was one without the date stamped.  I replaced it with the one I bought in 2012 that had the stamp, and it works fine.  It also still shows three green bars for condition so I'm happy with that.

This still doesn't explain why this new battery seems to have triggered the problem on the 7D, and why all 3 batteries were affected.  I dodn't know if the original 2 batteries were 3rd party made to look like Canon, or if the date stamp was a new addition later in production.

Well, the 7D has a buyer and the battery read issue was disclosed - told him I'd throw in a second battery.  Guess I know which 2 batteries I'll be including.

[Zathrum]

Had another fiddle with my 7D. Didn't manage a repeat of the 'life' seen with either battery. Camera is fine otherwise, no other side effects and I really do suspect the batteries rather than the camera.
Either way, I'll likely sell the 7D for a 7D2. Want that focus system and 10fps....

[Zathrum]

Bought a 7Dmk2 and two 6N batteries. All batteries report for duty in the mk2, none in the mk1. If mk1 is left empty for a few hours to a day, it responds to any battery inserted. Open the door for a moment and no battery is good enough.
Seems like a component short somewhere.
Will have it fixed I think and maybe a new 'mode' dial and use it as a backup.
Loving the mk2.... (Except the dodgy focus behaviour....)