Very often I find that Android Auto shows it is 'Searching for GPS'. If I disconnect the phone from the car, Google Maps has a GPS lock. When I reconnect it, GPS works on Android Auto for awhile, but goes back to Searching for GPS.
I am testing with a none magnetic car mount as I recall reading somewhere about a theory this is related to the compass calibration going off. I did three drives today without using my magnetic mount and the GPS didn't lose signal. Normally it would have after the first drive.
