# Problem with a Canon 420EX flash.



## brandonXcore (Mar 2, 2010)

I've been using this flash quite a lot for the past year and a half or so. Just recently, however, it stopped working all-together. It will not even turn on. I checked the batteries, the contacts, and they seem fine. Batteries are kept fully charged when needed to. It may be a simple fix, but as for now, I can't seem to tell what the problem is. Anyone have any idea as to what it may be?


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## keith foster (Mar 2, 2010)

My 580EX II will not power on with rechargeable batteries.  Try regular batteries to see if your recharges are not charging as much as they used to.


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## Garbz (Mar 3, 2010)

! keith for the love of god how can you accept an expensive product with such a "feature"! 

brandonXcore you seem to have a lot of your bases covered, but I do agree with keith on one core point. Try a different set of batteries. Fully charged batteries are quite different from working batteries


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## keith foster (Mar 3, 2010)

Garbz, I know.  I feel like an alcoholic just admitting he has a problem. 

Actually, I only tried one set of rechargeables, the ones I bought the day I bought the flash, and when the flash wouldn't power up I did all the trouble shooting and got online to look for help.  Someone suggested trying different batteries and all I had were alkalines.  When the thing powered up I was so thrilled I never tried rechargeables again.  

I need to try a different set of namebrand recharges just to see if I am going to be permanantly disabled or there is hope.


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## brandonXcore (Mar 3, 2010)

Keith, I took your advice and went with the alkaline batteries but still no luck 
It seems to be the actual flash itself. I tested two sets of rechargable li-ion batteries that are still functional and they don't work either. So weird...


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## brandonXcore (Mar 3, 2010)

Nevermind guys I fixed it. Dunno exactly how I did it because all I really did was use a multimeter to test all my batteries out and then I unscrewed the hotshoe contact off and screwed it back on. I'm guessing the solder for the power switch may be getting weak and by detaching and reattaching the hotshoe I knocked the connection back in place. I have no idea I'm no electronic specialist. But it works now. Yay.


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## pbelarge (Mar 5, 2010)

Sometimes by disconnecting and then reconnecting electronic gadgets, they will reset. Sort of like turning your computer off and on to clear it up.


I know this sounds off, but there are times when we perform what to us is a routine procedure, yet make a slight mistake. Then in trying again we do not even know what we did and it works. 
With batteries, one may not have been properly aligned...just a thought


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