I have a Nissan Leaf Tekna 2014. Today when I was going to start my car I could not open the door with my FOB. There were some slight light flickering as I locked/unlocked my car, but nothing else. So I used the manual key and got inside. When I pressed the start button every single light in the dashboard lit up, and it started beeping. "Key not detected" and "Low engine power" it said in the display. So I swapped battery, in both my FOB and it did nothing. I can open the charging hatch and put in the charger. The symbol lights up in the display, but the charger itself only stays on "Ready" and not "Charging". Does anyone know what might be wrong? Could it be an ECU that is defect?