2021 GMC sierra why has my-wireless Apple CarPlay stopped working, works fine when plugged in

Hello Sierra_Gmc1959,

Thanks for reaching out to Apple Support Communities. We see you have some questions about CarPlay and how it's not working with your car, and we'd like to help. We also see you came from the best article for this: If you need help with CarPlay - Apple Support

We also recommend looking over the 7th step in the article we provided, to see if your manufacturer can be of any assistance:

7. Make sure that your CarPlay stereo is using the latest firmware from the car manufacturer. Check your car's manual for more information.

If you still need help, we'd recommend reaching out to Apple Support to look into this further.

Regards.

Mine did too. Same 2021 gmc Sierra. Stopped about a week ago. It works when connected w a wire but nothing wireless. Bluetooth will still connect to the truck, just not CarPlay. Just did an update on my phone. Have to see if it fixed it.

The Wireless connection from my 2018 GMC to my IPhone has deteriorated over time, as well. I'm about ready to drop the wireless from my pickup, as it is useless to load anything on the phone while in the truck. I find if I "forget" the wireless it works better, even when I'm only getting 1 or 2 bars of cell coverage. Would be great to know if this is a phone settings issue, or the vehicle needs updates. I've received nothing, proactively, letting me know I should expect a performance decrease from Apple or GMC. Thanks, Dave

Follow up! I reached out to the Onstar Connection Team and they suggested, and performed, a wifi reset (completed by them, remotely) which looks to have improved the performance of Wifi for my IPhone in the truck. Something to try if you're experiencing the same performance woes. Thanks, Dave

Update did nothing. Still doesn’t work. Looking on other forums a lot of people are having issues w this on gmcs. For some reason my CarPlay works on a dodge van but not the gmc Sierra.