Same issue with my NX350H today.
• I Installed IOS 17.4 recently.
• started the car
• no automatic connection with my iPhone.
• went to “Manage Devices”
• selected my iPhone
• selected “Connect”
• screen faded out for a full minute
• then the “CarPlay Connection Error” displayed in a gold/yellow text box.
interestingly, BEFORE I selected “Connect” in “Manage Devices”, I checked the Bluetooth connection status on my iPhone and saw “connected” beside the Lexus. But as soon as I selected “Connect”, my iPhone’s Bluetooth connection reverted to “not connected”.
This is not the first time I’ve had connection failures.
I am not pleased.