580 EXII Pilot Light not coming on at event, Question regarding Cold Weather

[EIREHotspur]

Ok I basically had every Photographer/Videographers nightmare....equipment not working right at a Big event.

I was taking a photo of a large group of people at an event and left my 20D and 580EXII in my car for around 45 minutes beforehand.

When I brought it in and went to take the photos the pilot light came on and I took maybe 4-5 test shots in a row and then took the group shot I needed.
Of course I wanted to take 3-4 to be sure but the pilot light would not come on.

So hoping the one shot would come out (I knew by the viewfinder it was in focus and that the flash had captured enought detail in a very dark hall) I went home.

Now for an hour afterwards I took out the batteries and put them back in and tested it to no avail.

Then suddenly after that and another unload and reload of the batteries it starts working away as normal with the pilot light.
From reading of this problem on google I know it can point to dirty contacts or bad batteries but I tend to discount this.

MY question to others is in your experience can the 580 EXII or other flashes cease to work properly from not being in room tempreture for a while?
Thats the only conclusion I can draw...because this morning it still works fine...I hate having something you can't rely on though.

I am lucky and gratefull I got the shot I needed.

 

[egproductions]

You are correct, cold enough weather can definitely drain a battery especially rechargeable batteries so you will want to be careful and give the batteries time to warm up before using them.

What batteries are you using? I use Sanyo Eneloops with my 430EX II's and they are amazing. They last an entire event. Of course it's always a good idea to bring extra batteries in case something like this happens and they get drained for whatever reason. That's one of the benefits of speedlights...you can just replace AA batteries.

It's also possible that moisture built up in your flash from going from cold to warm weather. Try to replicate the situation and if you can, switch out the AA batteries for fresh ones that you know work and see if the flash functions then. If it doesn't then you know it's the flash going from cold to warm and not the batteries.