iOS 27 breaks wireless CarPlay connection with Smartbox 0242 on iPhone 17 Pro Max

Try this

Reset Network Settings on your iPhone:

• Go to Settings > General > Transfer or Reset Phone > Reset > Reset Network Settings.
• Note: This erases saved Wi-Fi networks and Bluetooth pairings, which is often required to clear corrupted network handshakes caused by major iOS updates. 

Clear the Smartbox 0242 Memory:

• Forget the Smartbox Bluetooth and Wi-Fi profile from your iPhone's settings if any remnants remain.
• Clear all connected phone history directly from the Smartbox 0242 settings/menu interface. 

Power Cycle Both Devices:

• Turn off your iPhone completely, turn your car off/on to fully reboot the Smartbox 0242, then turn your iPhone back on. 

Re-pair the Connection:

• Enable Bluetooth and Wi-Fi on your iPhone, pair fresh with the Smartbox 0242, and follow the on-screen prompts to allow wireless CarPlay.

If this is not working, you might need to give this as feedback to Apple so that they can look into. the issue. Please do that using this form

Product Feedback - Apple

I’m experiencing this issue as well, which seems to be related to the initial Bluetooth connection. 

Here is a workaround that consistently works for me:

Go to Settings > General > CarPlay on your phone and toggle your car off.

Turn on your car and wait for the infotainment system to fully boot up.

Toggle your car back on in your phone's CarPlay settings.

Manually trigger the connection from your car's dashboard.

If your car is already running, simply toggle the car off in your phone's CarPlay settings, try connecting from the car's dashboard, toggle the car back on in your settings, and then attempt to connect again.

I’ve had this same issue in years past. It has often gotten fixed in the first few os updates

Just an update. After the IOS 27.1 update everything is working good again

I got the same problem using an Android head unit. I had apple support on the phone and they checked my 16E and said the head unit firmware must be updated. I have done that and still the same problem. It works with usb but sometimes dropping the connection too. IOS 26 was working perfect

Similar problem but does eventually connect on both wired and wireless. It is now 3-4 minutes vs 10-15 seconds. Reset network settings, power cycled devices, hard reset on radio in car, deleted CarPlay profile. Nothing seems to improve it. I've submitted to Apple but looking into "downgrading" back to iOS26 on one of the devices until Apple gets it fixed.

It didn't last long. The problem is back again. It worked perfect with IOS 26.