5D Mark IV won't wake up after changing batteries in grip

[ldavis2718]

I have two 5D Mark IVs which are my work horses. They have both started having the problem where I go to change the batteries, and once fresh batteries are put in.... they won't wake back up.

I have sent the one camera into CPS for repair and I was told that the circuit board to the power supply had actually failed and so it was replaced. 

Well, it happened again on that same body just yesterday.,

Do grips go bad? Can batteries cause this issue?

I need all the help I can get because I cannot be on location and have both of my cameras decide to take a long nap. I have no idea how long the nap even is because I need to keep shooting and don't have time to dilly dally with it.

Any help is greatly appreciated.

[jrhoffman75]

Welcome to the forum.

Are you using a Canon battery grip or third party?

[ebiggs1]

"Are you using a Canon battery grip or third party?"

If not, that is the problem and could be the cause of the power board failing.

[ldavis2718]

We have all Canon certified gear. No 3rd party grips or batteries

[ebiggs1]

OK, that is good so that eliminates that idea.  How about trying a full reset of the camera?  You need to remove the clock button battery, too, and the main battery for a good while. Like 30 minutes or so.  If you have to reset the initial time and date it did reset.

[Waddizzle]

Yes, grips can bo bad.  They are pretty simple device, but anything can fail at anytime.  I am certian you have checked to make sure tha tthe grips are fully tightened to the body.  So, I am going to rule that out.

This leaves the grips and the batteries themselves.  The obvious question is does the camera(s) power up without the grip.  Be srue to re-install the battery compartment door.  AND, do double check the door to the memory card compartment./

You say this happened with a new set of batteries, but what about the old set?  Did you throw them away?  I can understand if you did.

[ldavis2718]

When I said new set I meant "freshly charged". Still rocking the same batteries.

I will definitely try just doing a singular battery next time in the body sans grip as I have a sneaking suspicion this is the problem as well...and or I just need a complete new set of batteries. The only reason I don't believe it is the batteries is bc they will then work on a different body.

[ldavis2718]

The clock button battery? Honestly, and maybe this is super ignorant of me, but I didn't even realize there was one in there. Where is that guy hiding?

[Waddizzle]

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@ldavis2718 wrote:
The clock button battery? Honestly, and maybe this is super ignorant of me, but I didn't even realize there was one in there. Where is that guy hiding?

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I don't think the more recent camera bodies use a clock battery.  They seem to use an onboard capacitor to hold a charge to power up the clock.  You should be able to completely reset the camera, right down to the date and time, by removing the battery, turning on the camera switch, and holding the shutter fullly pressed for at least 10 seconds.

[ebiggs1]

I don't have a Mk IV but on my Mk III the clock battery is below the input/output door on the side of the camera. The newer MK IV may not have one. If it does not it makes a hard reset more difficult. Your only recourse is the menus. Tools, clear all settings and clear all custom settings. Holding the shutter button down with out a battery may or may not work but time always does. It will take some time to drain all the remaining power, at least an hour or more.