Check the 8 pins ic, is it somekind of powersupply / controller / buck boost smps .... ka34xx number it has an coil and rectifier diode near it, maybe busted
![Huh? ???](https://www.eevblog.com/forum/Smileys/default/huh.gif)
Search fo any 3 pins regulator transistor look a like ...
Under the v3.0 you have an pic xxx controller, hope it is not busted
Ask the company for an schematic under non disclosure agreement ??