I do not know that model, but in almost all the panasonic modular the micro must have 5v voltage on these pins, and if you do not register anything, there is a short in these lines. I recommend that you isolate these lines to see which one has the problem. With the modular disconnected and these lines isolated from the rest of the components, check ohmeaje, you should dial up to 2 to 5kilos if it gives you very low reading is the micro.But do not be scared usually are the audio outputs or some short in mechanism motors or some slip in your symmetric line (voltage + and -)