My 2016 500e recently began displaying the message'service charging system'. Initially, I could fix it by turning the car off and on several times. However, this is no longer working. The car still makes the usual tapping sounds when I open the door or plug in the charger, but it is now stuck in "Not Ready" mode and refuses to charge or drive. I've tried every troubleshooting step I know of, but nothing has solved the problem. What should I do next?
