I have both a smart car charger and the smart car health monitor and my two devices never connect automatically when I start my car. However, they work fine if I start the Zus app. I am running Android 9.0 on an Essential phone. I normally have a smartwatch connected and my stereo connects automatically when I start my car.
Also side note, on the forum sign up page, Ottawa is in the list of provinces. Ottawa is a city, that would be like having New York City as a state. Just thought I would point that out.