Same exact issue. I get it with Waze and Google Maps. As soon As you close the screen the app closes on CarPlay within 10 seconds. Both apps react exactly the same. Screen then goes blank until you reopen the app on your phone. Apple Maps works fine (but it’s terrible) Also noticed ny iPhone 15 pro max runs super hot when running Waze or GMaps. Maybe this is Apple‘s way of forcing users to use their platform.