dont know if this is the right place for this since its not a mod of a pv lol i have a 510 type auto cig that had a cigarette pack like charger/holder for carts and battery. it was not consistently charging my 510, so I busted it open and removed the usb plug and wiring as well as the connector to the battery for charging. i had some njoy xpress rn4081 usb chargers lying around, so i cut off the batt connector end and wired it up to the same colors on the 510 type setup. When i connect the battery, i get no charging. I dont understand why. Can anyone help? Does the usb plug contain some kind of circuitry to charge the battery? (it was destroyed stupidly by me lol) The rn4081 charger has some kind of circuitry board in the connector end, but it also has a led light that tells about charge readiness. The 510 did not. The led in the battery is what tells whether its charging or not. Thanks for your help!