When I press the Power button to turn off one of my K3s, the LCD screen stays lit but shows no information. The P3, powered by the 12v outlet at the back of the K3 does go off. Of course, if I turn the power supply off, the LCD screen goes dark. However, when I turn the power supply back on, the rig comes back on also. 73, Ken, K6LA / VY2TT