I have pretty much the same car as you. 2016 LT w/ 7" MyLink. Late last week I plugged in my phone and tried Android Auto - failed to launch. It has been working fine for a long time - especially well since the overhaul beta that is now official. I had been ignoring it but seeing your post I decided to sort it out. Tried again this morning and on connect it still failed to launch. I cleared the data and cache via settings/apps and still failed.
I try not to go small when fixing things like this and go all out:
1) unpaired/deleted my phone from MyLink and disconnected USB cable
2) uninstalled Android Auto (I was on the latest version 5.0.500223)
3) restarted phone
4) Bluetooth paired to car
5) Plugged in USB cable to car
6) MyLink detected AA capable phone
7) downloaded AA automatically following prompts
8) started AA, granting all permissions
9) launched map, tested voice, tested fine
I have since started and restarted the car, tested fine. Restarted phone and car again, all auto launching fine.
I am still on AA 5.0.500223 and running Android 9 with Dec 2019 security patches. Galaxy S9.
I try not to go small when fixing things like this and go all out:
1) unpaired/deleted my phone from MyLink and disconnected USB cable
2) uninstalled Android Auto (I was on the latest version 5.0.500223)
3) restarted phone
4) Bluetooth paired to car
5) Plugged in USB cable to car
6) MyLink detected AA capable phone
7) downloaded AA automatically following prompts
8) started AA, granting all permissions
9) launched map, tested voice, tested fine
I have since started and restarted the car, tested fine. Restarted phone and car again, all auto launching fine.
I am still on AA 5.0.500223 and running Android 9 with Dec 2019 security patches. Galaxy S9.
