I purchased the full graphics smart controller and got it working, had to upgrade to latest marlin to get it to go but anyways. Once it was working i noticed as soon as i disconnect the USB cord from my laptop the screen on the controller stays bright blue but the letters on the screen are so dim you can just barely see them at all. I can navigate through the menus and move the printer axes and such but the screen is just very dim. The adjustment pot doesnt do much.
Using Ramps 1.4 with Arduino and Marlin.
Am i losing voltage somewhere or is this a somewhat common issue? Found lots of posts about dim screens but nothing thats related to the USB.