Battery discharge warning

Hello, I’m new here and have a technical question about the Navi of the i30 PDe’s. I have the i30er in the Passion variant. However, without the Navi, only with the 5″ color display. I have now built in a Navi, that also comes from an i30 PDe. So the Navi what the higher equipment have. The connections are almost the same for the radio, however after about 10 min driving always comes the warning that the system should be operated only with running engine, otherwise a battery discharge threatens. I know it’s because of a PIN, which gives the radio a signal, whether the engine is on or not. My question would be now, if there is a possibility that you can’t get this message anymore? All workshops and Hyundai themselves don’t know how to fix this. But I don’t want to believe that so correctly??. I hope someone can help me.