I have a 2 battery bottom door regulated mod that broke. It would start up but when trying to fire it reads check battery, Ive read about this as a wismec problem though i was not using one i thought it must be the same issue. So i hopped online and found a how to for the 200rx or something it stated the issue was the pin that makes sure the mod is closed properly. They proceded to solder both the brass tabs with some zink raising it up and allowing for connection with the pin. I thought this was a little permanent for a basic troubleshoot. so i found thin copper wire which i fassioned into the slot that needed to be raised to see if this was infact the problem. And go figure it was that. So i removed the batteries and the piece of copper(carefully to avoid a short with the positive side of the one battery) and the spring that was lax suddenly recoiled like new. There is no need to solder it now and it works. So maybe this works for one of your tabled mods as it did for mine. Just be careful when using conductive materials near batteries.