Google’s automotive operating system, Android Auto has had its issues over time but consistently the best experience has come with Google branded phones — until recently. In a recent update Google inadvertently broke the connectivity with Pixel 2 and Pixel 2 XL phones but they have a fix ready to go.
Since the last update more often than not connecting your second generation Pixel to an Android Auto head unit has resulted in a message popping up saying that:
Android Auto cannot connect right now. When it is safe to do so, please check your Android phone.
The obviously prevents any Android Auto interface from loading and goes nowhere. It only happens with the Pixel 2 XL I have found (OnePlus 5T works fine) and it can be fixed by unplugging and re-plugging the USB cable a few times (if it does not work the first time). Google have found what they broke though and are endeavouring to fix it with the bugfix rolling out in the next security update.
While it is not known what they broke, and it is not the first time they have accidentally broken something in Android Auto with updates but to their credit they have fixed it each time. Hopefully the February patch brings a working bug-fix.