I have a 2021 Tahoe LT. My wireless CarPlay stopped working about a month ago as well. Coincidently the same day that AT&T had that nation wide service outage. Last month I had an iPhone 13 up to date and it would not connect wirelessly to CarPlay but it would connect with a cord. I had to get a new phone at the end of February and ended upgrading to the iPhone 15 and figured maybe that’ll fix the issue. Nope, new phone still doesn’t connect either. I’ve tried deleting phones and reconnecting them to Tahoe wirelessly, trying other iPhones from family members, completely rebooting the Tahoe sound system and even completely erasing everything and still no fix. I do have a maintenance appt tomorrow so I’m hoping it’s just a software update that’ll fix this.
Edited to add: my phone does connect to Bluetooth but not to wireless CarPlay
If you "Disconnect" the phone after the vehicle starts up and fails the connection...can you then reconnect it?
Try these steps, beginning from a powered off vehicle:
1) Enter the vehicle, with your phone, and start it.
2) Wait about 30-45 seconds until you see your phone is Bluetooth connected, but not CarPlay connected
3) Tap "Phones" icon on the vehicle infotainment screen
4) Tap "Disconnect" under the icon on the vehicle infotainment screen corresponding to your phone
5) Wait for the disconnect to happen
6) Tap the CarPlay Icon On the Infotainment screen corresponding to your phone
7) You should see it connect now.
This was my workaround when on Y168 when I had issues...connection would be solid after that. Usually had to repeat 1-7 above at every startup.
Y171 has made the autoconnect process at startup work about 95% of the time now.
There must have been some bad timing sequence in the firmware...
Let us know if that works.