I would suspect a wiring issue, but it is impossible to say from just a pic. Only 11.5V showing at the unit is troublesome to me. I use a 20AH (or 50 AH) lithium with my 93svUHD and PLS, and I never see less than 12.8V. I am also not using a ground wire nor the ferrite, but 93 wiring and power is independent of TM, and well separated from TM wires to avoid crosstalk.