CarPlay unresponsive after iOS 18 on GMC Terrain

Not true, especially the GM reboot issue.

There should be nothing an iPhone could possibly send the GM head end that could cause it to reboot - so that will need to be fixed by GM.

The wireless CarPlay issue sounds like Mazda did not properly implement things.

Many engineers at Apple drive any number of vehicles, so if these issues were iOS issues that happened across all models of a particular vehicle, Apple engineers would have tripped over them by now.

GM told me I needed I take it in to get diagnosed…for at minimum $250 with no fix guaranteed.

For anyone curious, I did also contact for an off-market stereo replacement and apparently Terrains have one of the few stereos that cannot be fitted for any other stereo!

So unless Apple and GM decide to do the right thing with getting numerous complaints…we have essentially said goodbye to CarPlay lol

This is happening on my 2020 gmc sierra as well. Very annoying. Tried to restart my phone it worked for about 20 minutes and now keeps rebooting my infotainment system.

It’s not a gm problem. It’s an Apple problem. After iOS 18 it started. Apple needs to fix it

It is not a gm problem. It’s an Apple problem. It’s on lots of other car manufacturers not just gm . Stop pushing fake news. It’s an Apple problem. Ok . Not a gm problem

Check the GMC forums to see if it’s happening to a lot of people. There will definitely be threads about it if it is. No issues in my 2022 Buick Enclave or our 2024 GMC Arcadia so not sure if it’s necessarily a bug affecting all vehicles under GM or necessarily a full fledge iOS 18 bug affecting most users (GM has been so slow with proving head unit updates period from my experience so I always hold my breath if a new major iOS update will have trouble playing nice…especially if we need GM to push out an update because they will take their sweet time if they do it at all 😂). I also haven’t had any issues in a Toyota that’s in the household or 2 Nissans so far. I would wonder though based on your situation if it’s possibly an issue specifically with your car head unit or firmware even though it is currently up to date. Usually when it’s an issue from the iOS or Android OS it won’t work at all…that’s been my experience in the past at least. Is this happening with the iPhone 13 that shows under your post? Just curious because it may matter if only certain iPhone models with the iOS 18 update seem to be having issues versus the iPhone 16 models (my lack of issues has been with the iPhone 16 Pro Max and the 15 Pro Max on iOS 18…both using wired and wireless CarPlay but it seems like someone else posted they were having issues with CarPlay using one of the iPhone 16 models in maybe a VW recently). Not sure if doing a restore on your iPhone will help but I know if you contact Apple Support it will be one of the troubleshooting steps if they have determined that there is a bug that can’t be resolved until an iOS update is released.

Talked to apple engineer for over an hour of trouble shooting and problem solving, we got nowhere. However it is definitely a problem with CarPlay but one that GMC (or your car maker) needs to put an update out to fix.

It was suggested to me to reset my iPhone to a previous iCloud backup with iOS 17 until an update is available. I also found if I play my music and have my map running on my phone but disable CarPlay when I plug my phone into the car, my music will still play (CarPlay crashes without it being disabled and Bluetooth won’t stay connected) so that is something to try for now as well.

I contacted GMC online and was told to call the dealership I purchased the car through to ask about an update and report the problem. That’s on tomorrow’s list! Will report back if I think of it. But so far the best suggestion I have is to contact your dealership as well and hopefully many reports will get them moving on an update!

I have the same issue in the 2024 terrain. It Is happens sometimes, but when it happens I have to power off the car for a few minutes to use the system again. It is very annoying, because it usually happens when I am on the road and the screen goes black without response until the vehicle is turned off for several minutes.

If it works on any other manufacturer's head end, it's not Apple's issue.

Lots of auto manufacturers outsource their head ends to third parties; it's likely the same OEM provided the software for all the misbehaving vehicles' entertainment systems.

There should be nothing that any device can send a head end to cause it to reboot, as there is not a "reboot head end" command in Apple CarPlay.

Pure and simple, if the head end reboots for any reason, it's a bug in the head end.

I have a 2019 Camaro as and after iOS 18 update there is a problem with car play . The system will work for 2 or three seconds then freeze and restart . I can’t believe Apple is not going to fix this . How can I go back to iOS 17. This is terrible . Apple told me to go to my car manufacturer and I did and 200.00 later they said it was a problem with my phone not the car and I need to contact Apple . So when I contact Apple they say it’s not my phone it’s the car . I think you get the picture I’m just getting passed back and forth so frustrating

No, I do not; in fact no one here not specifically identified as an Apple employee works for Apple.

Decades of software experience is what causes me to say what I do.

For example:

Say the head end has a bug where if you add 2 + 3 it calculates it as 5, but if you add 3 + 2 it is calculated as 6.

It's not Apple's responsibility to make sure their software never tries to add 3 + 2, even though they didn't in a previous release.

As I said, there is nothing in the CarPlay spec to tell the vehicle head end to reboot, so if anything the phone can send does, it's a software bug that must be fixed by the manufacturer.

Worse, now that it is known something can cause it to reboot, that's a security issue known as a "denial of service" attack. Researchers can duplicate the sequence causing the issue and force your vehicle's head end to reboot continuously whenever they are in range, as it can be exploited wirelessly.

Welp 18.1.1 on phone. Car is updated. Same thing is happening as before. If the map is going and music playing or I get a phone call/text. Here comes the reboot for the GMC terrain - black screen or the car is stuck on one note of a song that sounds like it’s skipping. HOPEFULLY the 18.2 comes out sooner than later I don’t have a GPS and that stinks when they are on your phone plus I hate listening to the radio. Plus safety hazard. Really starting to hate CarPlay.

I have the same issue with my Ford Explorer. The fix for me is to reset bluetooth on my iphone and hope carplay will reconnect without rebooting the phone. Odd thing now is my Airpods won't connect via bluetooth until I reset bluetooth on my phone. Common denominator is the iOS 18 upgrade.

Why are you blaming CarPlay when it's clearly an issue with your GMC?

Even if Apple changes things so the reboot no longer occurs, the fact is there is nothing in the CarPlay interface that commands the head end to reboot, so it's a bug in your head end.

Apple may or may not alter CarPlay to not trip over the bug, but it's still a GMC bug.

Did anyone find out why?? Same thing is happening to me.