CarPlay not working on Alpine iLW-w670 with iOS 18

Apple is neither here, nor will they fix an issue with your Alpine head unit. It may need a firmware update to bring it into sync with iOS 18 CarPlay. Check with Alpine to see if said firmware update is available.

Review the Alpine instructions for using CarPlay and Use CarPlay with your iPhone - Apple Support

Try This

1. Go into your iPhones settings and turn off everything related to CarPlay and restart the iPhone.
2. Do a factory reset on your car's screen.
3. Go back to the iPhone and reactivate CarPlay.
4. Back to the car's CarPlay set-up menu: When prompted, select Forget This Device.
5. Then, re-sync your iPhone to CarPlay.

It is up to Kenwood to test their implementation of CarPlay with new releases of iOS (which they have access too), and issue any relevant firmware update to your head unit. Apple has no control over what Kenwood does and if Apple makes changes in the current CarPlay, Kenwood should have caught it — unless your head unit is older than what Kenwood now supports.

It will be a cold day in hades before Apple issues any apologetic missive about changes to its operating systems impacting older third-party devices.

This is also the case with the Kenwood eXcelon DMX957, since the update to iOS18, carplay cannot connect. this is on an iPhone 12 Max Pro. breaking backward compatibility without acknowledging it is not cool, Apple. This was working fine on iOS 17.