Very saddened and disappointed to see yet another round of Android Auto issue.
Various site already reports massive issues with the new S21 and Android Auto not working.
I am facing same issue as being reported: Android Auto doesn't connect or recognize your Samsung Galaxy S21 - other phones with same cables works flawlessly - huge disappointment!
Try the shortest cabl;e you have. I was reading a thread on the Razr 5G forum where they needed to use like a 6" cable while they were awaiting a software fix. Of course some users had no issues but it did resolve it for others.
Galaxy S21 Ultra 512g(VZW), Galaxy Book (original, VZW), Tab S4, Galaxy Watch3 (VZW)
Same problem here with my s21 and my kia niro 2020. It doesn't connect, but works fine with my pixel 3.
Something must be done quickly by samsung, it's unacceptable :face_with_steam_from_nose:.
I have only tried Android Auto installed in my 2019 Equinox once with my Galaxy S21+. It was working well with my S9+. I exited the app because no matter what adjustment I made the audio was very low. I did not have time to play (hard and dangerous to trouble shoot while driving). I hope all the issues are fixed soon as I have a long drive coming up and use Android Auto for Waze and Audible!