The CarPlay app comes with new features such as lane guidance, the current speed limit, alternative route recommendations in iOS 11. I have used an iPhone 7 running iOS 10 and the feature works fine with my 2015 VW Tiguan car. However, after I upgraded the device to iOS 11.1 and connect them through a cable, the car takes a long time to recognizes it while the app is not working at all. It just fails to respond to remote commands in the car console and the source of music disappear in Now Playing.
I switch off the do not disturb while driving function, but that doesn’t fix the issue. The Siri still will not read my texts, and the iOS 11 broke my CarPlay on a 2017 Nissan Maxima. It may be occasional compatibility issue with certain audio systems with a new version of iOS.
You could try any of the solution for that:
* It may be hardware issue with the cable.
I used the original cable coming with my iPhone 6 and Carplay just fail to start. Then I change the lighting cable to the new from my iPhone 7 and it works perfectly. The old cable seems to be not compatible with iOS 11.
* If you do a hard rebooting with your iPhone, the carplay will become normal.
Press and hold the Top or Side button to get the slider appears, and drag the slider to turn your device off completely, then press the same button to power the device on again.
For iPhone X or on iOS 11, you can also open the Settings app, go to General, and tap on the Shut Down option.
* Reset the iPhone as new device
First restore your phone from a back up, then open the Settings app, go to General> Reset, tap Reset network setting, and follow the on-screen introduction to complete the reset process.
You can also downgrade one step to iOS 10 until the Apple release the path for Carplay function.