From firmware 2.1.0 and companion app version 2.22.0, we introduced a "GM Fix" to workaround this issue. Please enable it from the "solid blue" troubleshooting flow in the companion app (help and support --> troubleshooting).

On firmware < 2.1.0 you can use the following solution:

  1. Clear cache and data of Android Auto
  2. Enable Android developer settings on the phone:
  3. Enable USB debugging in Android developer settings.
  4. Connect phone to PC
  5. Run the following adb command in terminal: adb shell setprop true
  6. Clear bluetooth devices on head unit (car)
  7. Plug in AAWireless and pair up

For reference: