I just upgraded my Motorola Razor to a Samsung S21 Ultra. My old Razor was able to send text by simply pressing the voice button on my steering wheel of my 2017 GMC SIerra and just say message wife, also andriod auto was not installed on my Razor. But on my S21 ultra I have andriod auto and google assistant installed and I cannot simply press the voice button on my steering wheel and send a text unless I have a USB cable plugged in. I have wireless andriod auto enabled. I can recieve and make calls and listen to texts without the USB cable. The only issue I have is I cannot send text without a USB cable plugged in. My S21 has andriod auto 6.4.611714 and is running Andriod version 11.