My favorite, 1st XL diamond - purple with a purple led has died. I think that the switch got stuck open. I put fresh cart on the battery, sat it down for a minute while I went and got something to drink, and when I came back and picked it up, it was flaming hot. And I could hear the cart sizzling! I took it off, tried the cart on a different battery -toast. And my purple XL no longer does anything. Luckily for me I was able to quickly take advantage of the extended 40% sale and order a couple of new ones. Been vaping for 18 months, and that's the first time that has ever happened.