5d3 issue - wont turn on

muvro wrote in post #17846347
Thanks for the advice guys.

So I pulled the cmos battery and left it over night in the car.

This morning, I replaced the cmos batt, fitted a lens and installed freshly charged battery. Switched on, nothing. Pressed a few buttons and it came to life. But it's glitchy as hell. Switch it off, didn't come back on. Tried again, on it came. So I took it out for some shots, top and rear dials worked intermittently and the viewfinder info was flashing and where the numbers normally show, all of the digits were a single dot going in circles and doing this only when half pressing the trigger.

- So to clarify the weather, the humidity was over 90% all day yesterday (24hrs).

- The camera was always either in the car or the tent, so i would be pretty confident it wasn't internal condensation. Temp was 21-22 for whole 24hrs. Just a lot of rain.

My thoughts,

- Is it possible for me to do a firmware update? (I don't know why, just an idea, as it feels to me like it's a program issue rather than a mechanical issue)

- if not, it's off to canon. If it goes there, I'll get them to sort out the flash slide corrosion and the difficult video/still switch.

I'll report back if it comes good.

Updating the firmware when it is flakey like this would be very risky IMO.

I would not leave it overnight in the car - serious risk of condensation.

Excellent point about the firmware!

Left it over night, turned it on and it worked perfectly. Played with it a bit, then the viewfinder info started playing up, at the same time, the jog dials and most buttons stopped working again. Looks like it's off to canon.

I figured leaving it in the car was better than in my camp trailer. I should also point out, my 70d has been with me in exactly the same conditions and it's perfectly fine.

It's got me stumped!

see if the battery contacts might have some dirt on them, shine a light in. You could use some clean cloth wrapped around a pencil or something like that if you see any dirt. Also see if they might be bent so they only get intermittent contact. Certainly an odd one. Could also be dirt/corrosion in the on/off switch I guess, maybe take the battery out and turn the switch on and off a couple of times, see if that maybe dislodges or rubs off some dirt or oxidation. Good luck!

I've checked I'll the battery contacts and they are clean.

The camera at the moment seems to be working. It glitched once today, but going slow with the dials and buttons (letting it think) seems to work. It's acting a bit like a pc with a virus. I'll see how it goes over the next couple of weeks, if it continues to be problematic, it's going to canon. I might even just send it in for a service anyway.

Thanks again to all those that offered advice. Really appreciate it.

Regardless of what the cause is of the camera misbehaving, if you are in very humid conditions for prolonged periods of time, then you should be doing what is necessary to protect your gear. There might be significant risk of fungus growth, corrosion, and electrical shorts.

Gear can be protected by keeping it at a temperature above the dew point or by storing in sealed containers with a desiccant.