40D - the Date/Time settings reset to default factory settings when switched ON|OFF

Can anyone advise me on what's causing this and how I address this annoying problem - before I launch the 40D body out of the 17th Floor apartment I am staying in!!

I used this camera with my 10-22mm lens on Saturday night for a 'family' function. The 'Law-of-Sod' kicked-in as this event was for a 50th Wedding Anniversary - so date/time stamping for this particular event was absolutely critical.

The only thing different in the way I used the camera, lens and flashgun was to attach the 2 x TT5 Pocket Wizards to my setup using the solitary 580ex II.

Of all ocassions it had to start happening on Saturday night!

There is a seperate battery that maintains date and time. Maybe it is going dead adn needs to be replaced?

krb wrote in post #10123667
There is a seperate battery that maintains date and time. Maybe it is going dead adn needs to be replaced?

Thanks Ken,

A what? - can't recall ever installing a separate battery. I just have the BG??? that I insert underneath this contraption.....

It's a small watch battery.

ETA: page 171 of your user manual. Says it is good for about 5 years and should be replaced if the camera forgets the date time when you replace the main battery.

Yeah definitely sounds like the date battery has gone flat. Its located right in front of the hinge where the battery door would go (but you removed it for your battery grip, but you'll see what i mean if you have a closer look). It has 'CR2016 3V' written on it, just put your fingernail in and lift up and it should pop out.

Really, I bought my 40D from Jessops in Brighton - UK back in 2008. I really do not recall installing a 'watch-battery' into this thing!
Any idea where to look for this - (all of my Manuals are in Brazil)

kimnkk wrote in post #10123721
Yeah definitely sounds like the date battery has gone flat. Its located right in front of the hinge where the battery door would go (but you removed it for your battery grip, but you'll see what i mean if you have a closer look). It has 'CR2016 3V' written on it, just put your fingernail in and lift up and it should pop out.

Thanks Kim,

Posted just after you... OK I will investigate further...............

Cham_001 wrote in post #10123723
Really, I bought my 40D from Jessops in Brighton - UK back in 2008. I really do not recall installing a 'watch-battery' into this thing!
Any idea where to look for this - (all of my Manuals are in Brazil)

You don't recall installing it because you didn't have to. You can get the manual from www.usa.canon.com

Ken you're a gent! - thank you.

I had absolutely no idea that these things had internal 'button-cell' batteries.
I'll have to stock up on these as the 5D will probably need a new one too!

What a relief. I thought this camera had finally broken!

(BTW: how do you 'close-off' a thread once a solution is found?)

Well, it's really not a solution until you swap the battery and test it, but I'm glad I could hopefully point you in the right direction.

No need to close off the thread. Other people might have questions or comments, somebody else may have the same quesiton, etc.

I just extracted this button-cell from its secretly and awkwardly positioned hide-out.
Lo and behold, as I have no spares, I replaced this chrome-coloured, flat, shiney and otherwise insignificant disc and of course, the date/time settings reset to default factory settings. As this has happened only since last weekend (after 2+ years of use), I am relieved at this instant resolution.

Cham_001 wrote in post #10123810
I'll have to stock up on these as the 5D will probably need a new one too!

"Stocking up" might be a bit extreme...you probably had a defective or old-stock cell in your camera...it is larger than most watch batteries and does less than most watch batteries need to do (no moving parts, no illumination) - IIRC, Canon claims they should last 10 years or so...preventative maintainance would probably be very good if you replace on in five years (though it seems not many people on POTN even keep a body for 5 years ) - BTW, you most likely have a similar battery in your computers for the same function..to keep the clock running.....have you ever needed to replace one before you junked a computer?

A computer could (and some may) have room for a rechargeable cell, but the tiny button lithium cells won't die like any rechargeable if it isn't plugged in for a few months...even the newer chemistry LSD (low self discharge) cells like Eneloops won't last 10% as long as a button cell in this kind of application.

Peace,

D.

Don't stock up on these back-up batteries. They are of litium type, and their self-discharge is about the same as the consumption from the camera, so they'll last about as long in their box as they do in the camera.
So once the one in the camera is dead, your stocked battery is probably the same.

Cham_001...regarding the time/date stamping...this can be modified by several exif programs....like the out of print but still available EXIFER free program. Had a situation where client went to europe with 2 cameras. The brand new one didn't have the date set. Swapping memcards between the cameras destroyed the timeline. We were able to reconstruct with EXIFER. Good luck, Paul

"... BTW, you most likely have a similar battery in your computers for the same function..to keep the clock running.....have you ever needed to replace one before you junked a computer? ...."
Delija: --> Very true! - just so annoyed with this 'glitch' and thanks for this prompt - Mantra: I must learn self-control

Anders:--> great tip, I'll just buy the 2, one for each body for now.

Paul:--> You have 'saved-my-ass'. I am downloading EXIFER right now. I will now be able to send these photos across for later today. They have called me 5 times over the past 2 days - and I have 'professionally' stalled them. They are not happy with me! - but this will change thanks to your advice

TO ALL: a huge thank you for all the advice and support. The level of knowledge on this forum is mind-blowing....

Afzal (aka- cham_001)