Since the S9 is a newer model, it's Bluetooth specifications are newer as well. The S7 runs Bluetooth 4.0 whereas the S9 runs Bluetooth 5.0. At this time, the S9 does not connect to older Bluetooth specifications and is only compatible with Bluetooth 5.0 or higher.
I just purchased the S9 and I have a 2015 Chevy Traverse. Bluetooth autoconnect is not working. Samsung also instructed me to contact Chevy. Before I did I was wondering if you found a fix? Otherwise I will take the phone back. Thank you.
Just upgraded from an S6 to an S9 and having this same problem. I've tried re-pairing the phone multiple times with no success. Phone doesn't auto-connect to my car, and if I open bluetooth settings and tell it to connect manually I get a "Cannot connect" error. I have to disable and re-enable bluetooth every time, sometimes multiple times, before it will connect to the car. S6 autoconnected every time with no issues
Phone: Galaxy S9 (SM-G960U)
Car: 2013 Subaru Impreza WRX
I've tried deleting the phone/stereo from each other's memory and re-pairing the phone at least half a dozen times with no effect. I can only get the phone to connect to the car stereo by disabling and then re-enabling bluetooth on the phone, sometimes it takes repeating this several times before it will work