Because Tiablo don't specified on the instructions that 5 mode switch will not work with 16340 cells, they only updated the page on cpf but don't explain the problem on the booklet.
So if you have problem with multi function switch contact tiablo.
I contacted them because I have here 10 flashlights that doesn' work with 16340 cells and they say that is not their problem but batteries problem.
I used only Ultrafire and trustfire cells not the cheapest one.
If they have problem with these kind of batteries they have to inform customers. I'm not satisfied of their service.
I'm the only here with that problem ?
It doesn't have anything to do with the quality of the batteries. It has more to do with the batteries output. The Ultrafire and AW batteries (really good batteries) are ~3.6/3.7 volt batteries; as you confirmed with your tester, they're a lot higher coming out of the charger (4.2-4.3 v). After a complete recharge (if I use the 3/5 switch), I have to drain my batteries (a little) in another light before putting them in the MA6. The MA6 works fine with primaries. I don't know for a fact, but it would probably do fine with some of the 3.0v rechargeables-I have no idea what the output of the Tenergy 3.0v battery is...it's a 3.0v vs. a 3.7v though.