This light is probably in the bin by now but I had a unexpected failure with mine EOS light (wife has the same model and worked fine when taking out of winter storage) and was wondering the same.
With some web browsing, noticed that someone had made a comment that the magnet switch on these lights fail regularly but were easily replaced (you undo the locking ring just behind the light switch to release and slide out). Could only find a replacement switch on ebay for 18 Euro plus shipping to Australia (if they would), so before taking the plunge to buy I thought I'd test the switch mechanism/light again with a strong magnet.
Turns out I could turn the light on and off by swiping the magnet (I think I rotated the magnet so the polarity pulls towards the switch but can't remember exactly), up and down in a "D fashion" mimicking the action the switch does, thus proving that it was the magnet in the switch that had failed, not the light as dreaded.
BONUS however that in the process of doing that, I'd re magnetized the switch mechanism, so I'd inadvertently fixed the problem during testing and didn't need to buy the replacement switch after all (which is also really good considering the older slide switch has been discontinued in the new model lights and aren't easy to find plus I have two of these lights).
I really like the light but for the $$ you'd think Mares would have used a better quality magnet in their switch. Magnets can lose magnetism through bumps, heat, cold or been incorrectly stored next to other magnets but then again could have just been a cheap crappy one to start with. Fortunately they are easily to re magnetize.
Hope this helps anyone else in the same position as I found myself in.
