Car GPS antenna re Carplay

[grasmere]

Does anyone know if:
When using an aftermarket CarPlay adaptor and my iPhone, is the GPS location signal coming “from the iPhone” through ‘location’ sensing or is it from the cars Nav GPS head unit?

wondering as my GPS signal using Waze or Applemaps is occasionally very slooooow to get accurate, eg sending me along a parallel fictitious route 200 yards away

Considering checking my head unit for GPS aerial connection

[Arne2]

My understanding of how CarPlay works leads me to assume that it is using the iPhone GPS, not the car's built-in. For one thing, CarPlay (and especially 3rd party wireless dongles) can't assume that all cars have Nav and/or GPS antennas (some early 718s w/o Nav lack the primary antenna that Nav uses).

Mostly what CarPlay does is to treat the screen and controls as external input devices. I believe all the real processing is done on the phone.

[Tom]

Paging @JetFuelOnly -- if I recall, he tried to get to the bottom of the various GPS antennas on the 718....

[grasmere]

Thanks guys, I ask because I would expect the cars GPS antenna to be the stronger v the iPhone so interested in what @JetFuelOnly may say . . .

[blueline]

Thanks guys, I ask because I would expect the cars GPS antenna to be the stronger v the iPhone so interested in what @JetFuelOnly may say . . .

I definitely don't know for sure but I feel certain that what Arne said is correct. Trying to get Apple Car Play's OS (or Android's Auto) to talk effectively with your car's device and its drivers would seem to be a nightmare scenario.

This snippet from Porsche regarding Apple Car Play seems to support what Arne said:

‘What is Apple CarPlay?’. It’s accessible in all current Porsche models, as well with the Porsche Classic Communication Management (PCCM) infotainment systems that are available for a growing number of earlier Porsche cars, Apple CarPlay allows you to connect your iPhone to your Porsche so you can access all your favourite mobile phone apps through your car’s infotainment system. By having these conveniently available to interact with on your car’s built-in screen, you can get directions, make calls, send and receive messages and listen to your favourite playlists or podcasts, all while still keeping your attention fixed on the road.

https://www.porsche.com/stories/innovat ... -a-porsche

I would guess that your lag might be due to the Bluetooth connection (which is always an issue) and/or just a bottleneck with back and forth data and command commucication. Even USB connections can impose bottlenecks depending on several factors.

[rowca]

My issue- new 2023 CGTS, w/ 1.4K on the odometer. Using iPhone hardwire connectivity via a USB cord plug-in, the CarPlay worked fine. I installed (hard wired) a Valentine radar detector using the rear view mirror for power. The CarPlay acted goofy providing wrong data and location. Spoke to the SA who reported that there issues with hard wiring and the Car's GPS system/antenna. I made an appointment but cancelled after doing the following:

For iPhones:
-Ensure iPhone has the latest update. Open Settings and tap General -> Reset -> Reset Location & Privacy.
-You'll need to enter your iPhone passcode to reset your Location Services.
-This will change your location and privacy settings back to the way they were when you first got your iPhone. Do this, and then try using an app like Maps or Weather to see if the location has been corrected.

Hope this helps. Good luck!

[blueline]

My issue- new 2023 CGTS, w/ 1.4K on the odometer. Using iPhone hardwire connectivity via a USB cord plug-in, the CarPlay worked fine. I installed (hard wired) a Valentine radar detector using the rear view mirror for power. The CarPlay acted goofy providing wrong data and location. Spoke to the SA who reported that there issues with hard wiring and the Car's GPS system/antenna. I made an appointment but cancelled after doing the following:

For iPhones:
-Ensure iPhone has the latest update. Open Settings and tap General -> Reset -> Reset Location & Privacy.
-You'll need to enter your iPhone passcode to reset your Location Services.
-This will change your location and privacy settings back to the way they were when you first got your iPhone. Do this, and then try using an app like Maps or Weather to see if the location has been corrected.

Hope this helps. Good luck!

Good info. Maybe the antenna is in proximity to the rear view mirror which was causing issues for others?

For what it's worth, I have hardwired Valentine One's (ver 2) in all our vehicles using Valentine concealed displays connected to a circuit that is only on when ignition is on. The circuit was determined and the V1 wiring was installed by Porsche. So far I've not had any issues with current or previous Porsches.

[signde]

I write iOS and Android software for a living so I am familiar with how all this works.

While CarPlay is mostly just an extension of your phone's screen, it does do some integrations with the car's systems. For the most part, your phone is the computer and the screen in the vehicle is just a second monitor for it. The phone is doing most of the work. However, Apple does require OEMs to meet a certain minimum spec and it's reviewed by Apple who requires certifying your design before you are allowed to support CarPlay.

If you go to the Apple WWDC presentation for Developing CarPlay Systems, you will see that GPS is listed as "Recommended for all CarPlay systems" and "Required for wireless CarPlay systems". So if you are wired, it will prefer the car's GPS but can fallback to the phone's GPS. If you are using wireless, it will rely on the GPS provided by the vehicle. Also for the record, wireless CarPlay is NOT Bluetooth. It uses Bluetooth for the initial handshake but then the connection switches to point to point WiFi, which can handle much more bandwidth than Bluetooth.

I learned the GPS behavior the hard way - when I moved an aftermarket Alpine wireless CarPlay unit from my Golf R to my 997 turbo, the GPS performance which worked perfectly fine before became abysmal in the Porsche. I ended up having to buy a newer Kenwood unit with a better GPS antenna.

Regarding interference from adding hard wired accessories to the upper center headliner, this is definitely a thing. There is someone who sells an OEM like dashcam for the Macan and right now the thread for that in the Macan Forums is littered with people complaining of electrical interference, some of it centered around wireless kessy being impacted.

[grasmere]

@signde

Ah very interesting, thanks for that indeed,

[blueline]

Great info signde!

It may seem backwards to most but I don't even fool with Android Auto and that would be the same if I was an Apple user too. My only real need when in my cars is nav and I am a dedicated Waze user so I just let the phone do that as a standalone device. I love it because I am not always having to sort BS connection and software integration gremlins. Plus, the distractions are greatly minimized if using my phone correctly and safely.

Simple can be good and after 40+ years of hard core PC use going back to DOS and Edlin along with my increasingly hostile carping at software, hardware and tech disasters that are ridiculously time consuming, I've learned to love embracing simple whenever feasible. The car cockpit is one such place when possible, at least for me. I don't want phone calls, texts or anything else that is not vehicle or performance related. (The exception is music except when in my GT4.) I'm in the car to (hopefully) focus on and have fun driving (especially if in a sports car) and/or to get from point A to point B at other times or when in my truck.

I do like Porsche's newer PCM's as standalone units for car controls, SiriusXM, etc. but I still limit use. The interfaces on today's cars are horrid sources of potentially dangerous distractions if used unwisely. I know many of you are adept at using them safely but, unfortunately, many drivers in today's world are not and they are bad accidents in the making.

I strongly believe in and support Andy Pilgrim's Traffic Safety Education Foundation and his very wise advice regarding deadly distracted driving. That kind of thinking is behind my semi-rant above. I've seen way too much bad out of distracted driving behavior and it needs to change if we want to keep our freedom to move about in vehicles that are under our control rather than via automation. My fear for those after I'm gone is an alternative world of mandated fully automatic driving - that's a dystopian horror that could happen in the coming decades.

Maybe not!!!