Here’s a couple of steps that worked for me when CarPlay stopped connecting after an iOS update:
Restart both your iPhone and Car: Sometimes, a simple reboot of both devices can fix any temporary connection issues.
Forget and Reconnect the Car’s Bluetooth: Go to Settings > Bluetooth on your iPhone, tap the “i” next to your car’s name, and select “Forget This Device.” Then, reconnect it by pairing the devices again.
Check CarPlay Settings: Make sure that CarPlay is enabled on your iPhone. Go to Settings > General > CarPlayand see if your car is listed. If it is, tap on it and select “Forget This Car,” then try reconnecting again.
Check for Updates: Sometimes, an iOS update can cause temporary bugs, but Apple usually rolls out fixes quickly. Make sure you're on the latest version of iOS by going to Settings > General > Software Update.
Reset Network Settings: If all else fails, you can try resetting your network settings. Go to Settings > General > Reset and choose Reset Network Settings. Keep in mind this will reset Wi-Fi passwords, Bluetooth connections, and VPN settings, so you'll need to reconfigure them.
Check your Car's System: Make sure your car’s software is up to date as well. Some cars need firmware updates to fully support the latest iOS versions.
If you’ve tried all of this and it still isn’t working, it might be worth reaching out to Apple Support or your car’s dealership to see if they have any additional suggestions or if there’s an issue with the update itself.