Quote from Guido on 16.09.2025, 18:40

Hi @mattsz,

before I attempt to analyse this… what are your detour behaviour settings?

Quote from mattsz on 16.09.2025, 19:04

Quote from Guido on 16.09.2025, 18:40

Hi @mattsz,

before I attempt to analyse this… what are your detour behaviour settings?

I don't think I've ever adjusted the Detour Behavior settings.  But here they are:

If I leave the route...

• Guide me to the first unreached via point

Skipping waypoints...

• Skip Waypoint button on map = "off"
• Ask to confirm skipping Waypoint = "on"

Auto-skip next Via

• Auto-skip next Via = "on" after 3 recalculations

Guide back to route

• Guide me back button on map = "on" (but "Don't recalculate" is not selected, so not applicable)

Regarding detours: it was my intention to follow the route exactly as it was planned.  I mentioned in my original post that I did end up deviating from the route, but that wasn't until we had ridden 161 miles of the 187 mile ride.  So for most of the ride, I don't think Scenic should have taken any detour actions.  There was one short leg of the ride where we ended up on a different road than planned, despite there being a waypoint on the road we missed.  I thought I was following the turn directions, and I saw no warnings about skipping waypoints, so I'm not sure why we missed that one segment.  Happy to send you the route and recorded ride if it would help...

Quote from Guido on 16.09.2025, 19:58

Thank you! with your detour behaviour in mind, there should be no reason for the turn by turn instructions to stop.

Furthermore, your location indicator was correctly positioned, but the recorded ride did not reflect that.

So, this sounds an awefull lot like a bug.

The only thing that’s weird is that I haven’t received any other recent reports about it.

I’ll need to look deeper into this.

If you could share the links to the route and the ride with me, that would be great.

Quote from Rods on 17.09.2025, 05:57

Over the last couple of weeks I’ve had a similar problem with the CarPlay device freezing when I’ve been following a planned route (I’m not sure if it has when I’ve just been tracking a route.). Sometimes it seems to have been cured by going into Overview and back, other times by switching the bike engine off and restarting. The only issue with diversions was a refusal to offer a new route once I missed a turning, despite detour being active in Settings.

Quote from Guido on 17.09.2025, 06:37

Hi @Rods... do you mean the same by freezing as @mattsz is describing where turn instructions freeze, but the map and position indicator still keep moving? Or was it a complete freeze in your case?

Quote from Rods on 17.09.2025, 10:12

Hi Guido

The locator arrow stopped moving and after a while I was asked if I wanted to resume the journey, despite me not stopping. Sometimes it resumed further along the route but then it wanted to take me back to all the via points which I’d passed in the meantime. Other times I’d try to encourage it by going to Overview or restarting the bike, as mentioned.

Best wishes

Quote from Rods on 17.09.2025, 10:23

Please note that I was using the phone with a (Carpuride) CarPlay device in areas where there possibly wasn’t a great phone signal, though my offline maps were up to date.

Quote from oldNNtheway on 17.09.2025, 17:39

OK. Good long laugh. Totally past my dispense date. Thru ‘60s daily work in electronic communications intercept and analysis etc etc…

Distorting GPS signals has been high priority in certain places and budgets for a long time.

Quote from Guido on 17.09.2025, 17:56

@mattsz. Thank you for sending me route and ride link over email. So... I've made my analyses, but I don't think you are going to like it 🙁.

Summary: I suspect there is a hardware problem with your GPS receiver.

The little jumps in the recorded tracks
I believe this is due to GPS inaccuracies. Normally, Scenic snaps the raw GPS location (as received from the GPS receiver) to the route. That snapped location is the one that’s being logged. If the distance between the raw location and the snapped location is higher than a certain threshold, the snapping will not take place and the raw location will be logged. I believe, that these little jumps is where that distance exceeded the threshold.
- The good news is that you can increase that threshold in Settings > Finetuning > Route recalculation parameters > Threshold distance. The default is 35 meters. I recommend increasing that to 45 or 50 meters.
- The bad news (maybe) is that there has to be a reason for this to surface all of a sudden. So, unless this also happened on previous rides (perhaps you can check a recorded ride from around a month ago for those little jumps), it means your GPS receiver became less accurate.

The big jump at the end
When Scenic receives a raw location, first it checks 3 things to determine if it should process that location.
1) The horizontal accuracy (mentioned above) should be lower than 60 meters
2) Speed should be between 0.85 and 85 m/s (3 - 300 km/h)
3) location timestamp should not be older than 5 seconds
If either of these things are not true, then Scenic considers the location not good enough to determine your position along the route, but it WILL advance your current position indicator. In other words, you will see your indicator moving on the map, but your the turn by turn instructions seem frozen. This will stay like that until a ‘good’ location is received again.
This raw-location-check is the only place in the code where this (frozen instructions, but moving on map) happens.

So this, combined with the little jumps, makes me believe that your GPS receiver is not always as accurate as it should be. Heat, due to high performant usage during the long ride (GPS receiver, full brightness), maybe combined with direct sunlight, might have something to do with degrading accuracy during the ride.

A GPS receiver becoming less accurate is rare, but it does happen. I myself had GPS receiver problems with a previous iPhone, and over the years I’ve had about 15 users with this problem.
To check your GPS accuracy, download this free app ( https://apps.apple.com/app/id1485889074 ) . When you start this app, it will show you the raw GPS information. The first value is Horizontal accuracy. This is the most important one. When you are outside it should be around 5 meters. I recommend checking this a few times on your next longer ride, especially when you see the frozen instructions again.

I hope I'm wrong, but it's better to check with this app.

The little jumps in the recorded tracks
I believe this is due to GPS inaccuracies. Normally, Scenic snaps the raw GPS location (as received from the GPS receiver) to the route. That snapped location is the one that’s being logged. If the distance between the raw location and the snapped location is higher than a certain threshold, the snapping will not take place and the raw location will be logged. I believe, that these little jumps is where that distance exceeded the threshold.
- The good news is that you can increase that threshold in Settings > Finetuning > Route recalculation parameters > Threshold distance. The default is 35 meters. I recommend increasing that to 45 or 50 meters.
- The bad news (maybe) is that there has to be a reason for this to surface all of a sudden. So, unless this also happened on previous rides (perhaps you can check a recorded ride from around a month ago for those little jumps), it means your GPS receiver became less accurate.

The big jump at the end
When Scenic receives a raw location, first it checks 3 things to determine if it should process that location.
1) The horizontal accuracy (mentioned above) should be lower than 60 meters
2) Speed should be between 0.85 and 85 m/s (3 - 300 km/h)
3) location timestamp should not be older than 5 seconds
If either of these things are not true, then Scenic considers the location not good enough to determine your position along the route, but it WILL advance your current position indicator. In other words, you will see your indicator moving on the map, but your the turn by turn instructions seem frozen. This will stay like that until a ‘good’ location is received again.
This raw-location-check is the only place in the code where this (frozen instructions, but moving on map) happens.

So this, combined with the little jumps, makes me believe that your GPS receiver is not always as accurate as it should be. Heat, due to high performant usage during the long ride (GPS receiver, full brightness), maybe combined with direct sunlight, might have something to do with degrading accuracy during the ride.

A GPS receiver becoming less accurate is rare, but it does happen. I myself had GPS receiver problems with a previous iPhone, and over the years I’ve had about 15 users with this problem.
To check your GPS accuracy, download this free app ( https://apps.apple.com/app/id1485889074 ) . When you start this app, it will show you the raw GPS information. The first value is Horizontal accuracy. This is the most important one. When you are outside it should be around 5 meters. I recommend checking this a few times on your next longer ride, especially when you see the frozen instructions again.

I hope I'm wrong, but it's better to check with this app.

Quote from Karlchen on 17.09.2025, 21:33

Hallo,

 

Mich erinnert das an mein Problem Anfang dieses Jahres.

Mir ist immer während der Navigation nur am Motorrad der Pfeil links neben der Strecke und zurück gegangen. Das alle paar Meter.

Im Auto war alles okay.

Nachdem ich den GPS-Sender aus dem Motorrad eingebaut habe, war der Fehler behoben.

Es gibt dazu hier einen Chat.

Vielleicht hilft das.

 

https://scenic.app/forum/topic/extreme-probleme-mit-4-18/#postid-12607

 

Beste Grüße

Quote from mattsz on 18.09.2025, 04:17

Quote from Karlchen on 17.09.2025, 21:33

Hallo,

 

Mich erinnert das an mein Problem Anfang dieses Jahres.

Mir ist immer während der Navigation nur am Motorrad der Pfeil links neben der Strecke und zurück gegangen. Das alle paar Meter.

Im Auto war alles okay.

Nachdem ich den GPS-Sender aus dem Motorrad eingebaut habe, war der Fehler behoben.

Es gibt dazu hier einen Chat.

Vielleicht hilft das.

 

https://scenic.app/forum/topic/extreme-probleme-mit-4-18/#postid-12607

 

Beste Grüße

@karlchen - thanks for that info... my issues are different than yours were, but mine could certainly be caused by a GPS accuracy problem...

Quote from mattsz on 18.09.2025, 07:48

@guidomm - Thanks for putting in the work here!  I have no reason to dispute your conclusion that GPS accuracy is my problem... in fact I have some additional data which may support it.  If nobody minds, I'll continue this discussion in the hopes that a resolution might be found, or at least future readers with similar issues might understand what's happening.  Apologies for the length of this post...

Quote from Guido on 17.09.2025, 17:56

@mattsz. Thank you for sending me route and ride link over email. So... I've made my analyses, but I don't think you are going to like it 🙁.

Summary: I suspect there is a hardware problem with your GPS receiver.

The little jumps in the recorded tracks
I believe this is due to GPS inaccuracies. Normally, Scenic snaps the raw GPS location (as received from the GPS receiver) to the route. That snapped location is the one that’s being logged. If the distance between the raw location and the snapped location is higher than a certain threshold, the snapping will not take place and the raw location will be logged. I believe, that these little jumps is where that distance exceeded the threshold.

Interesting… but I’m still unclear why this is occurring - aren’t the raw locations are correct throughout, since my location displayed on the map is accurate? Maybe I don’t understand the difference between “logged” locations and ride recording data.

- The good news is that you can increase that threshold in Settings > Finetuning > Route recalculation parameters > Threshold distance. The default is 35 meters. I recommend increasing that to 45 or 50 meters.

Also not sure what increasing the route recalculation threshold distance would accomplish, since there is no route recalculation happening.

Aside: I’m curious: when following a route, if I deviate from Scenic’s instructions, especially a “gentle” deviation like a highway exit which might not register right away, Scenic, I think, shows my location as on the route until I deviate a certain amount, then my location on the map “jumps” to the correct spot. Does this behavior demonstrate how Scenic “snaps” to the route until the threshold distance is reached? Should we expect the recorded ride to indicate this “jump?” I’m pretty sure I can see places in my recorded rides where this has occurred…

- The bad news (maybe) is that there has to be a reason for this to surface all of a sudden. So, unless this also happened on previous rides (perhaps you can check a recorded ride from around a month ago for those little jumps), it means your GPS receiver became less accurate.

I’ve looked back in my archives and scanned some recorded rides over the years. I find that most of the long rides have only very occasional jumps… like one or two over 100 miles. Most of these are small; just a few are longer straight lines between distant points on a road.

I'd be curious to know if there's a normal number of little glitches that everyone sees over a long ride, or whether some people never have any issues at all.

The big jump at the end
When Scenic receives a raw location, first it checks 3 things to determine if it should process that location.
1) The horizontal accuracy (mentioned above) should be lower than 60 meters
2) Speed should be between 0.85 and 85 m/s (3 - 300 km/h)
3) location timestamp should not be older than 5 seconds
If either of these things are not true, then Scenic considers the location not good enough to determine your position along the route, but it WILL advance your current position indicator. In other words, you will see your indicator moving on the map, but your the turn by turn instructions seem frozen. This will stay like that until a ‘good’ location is received again.
This raw-location-check is the only place in the code where this (frozen instructions, but moving on map) happens.

Not sure what you mean by #3, “location timestamp should not be older than 5 seconds.”

So this, combined with the little jumps, makes me believe that your GPS receiver is not always as accurate as it should be. Heat, due to high performant usage during the long ride (GPS receiver, full brightness), maybe combined with direct sunlight, might have something to do with degrading accuracy during the ride.

I suppose heat could be the problem, but I’d be surprised. I have a “naked” bike, and my phone mount on the handlebars leaves the phone directly in the stream of moving air. Ambient temps on my recent rides have been in the high 60ºF (15C) range, with partly cloudy skies, so not always bright full sun.

A GPS receiver becoming less accurate is rare, but it does happen. I myself had GPS receiver problems with a previous iPhone, and over the years I’ve had about 15 users with this problem.

I’ve used two different iPhones since becoming a Scenic user; I never noticed a difference when I upgraded to my current iPhone SE. I remember a discussion here awhile ago about wireless chargers interfering with GPS signals - I think that was primarily an iPhone 11 issue? My investigations at the time led me to conclude that I wasn’t having that problem. But… maybe? I used to plug my phone in, but in May of 2022 I installed a Quadlock handlebar wireless charging unit. I don’t see any dramatic changes in recorded ride glitches at that point in time.

But the other day I was on a ride whose recorded data appears to show relatively few “little” jumps, but a fair number of “big” jumps. It seems strange: there were a few big jumps just minutes into the ride (when the phone probably should not have had the chance to heat up yet), then miles and miles without any issues. Then suddenly I noticed a number of long jumps as they were occurring - I can’t fathom why the issue would appear to be so intermittent. Anyway, at that point on the ride, I chose a major direction change at an intersection, and I switched off the wireless charging unit. The glitches stopped. After 10 miles, I turned it back on, and the glitches began again (just small ones this time, though - deviations rather than just a long straightening of the recorded line). But then long stretches of many miles without any glitches.  It's a mystery.

To check your GPS accuracy, download this free app ( https://apps.apple.com/app/id1485889074 ) . When you start this app, it will show you the raw GPS information. The first value is Horizontal accuracy. This is the most important one. When you are outside it should be around 5 meters. I recommend checking this a few times on your next longer ride, especially when you see the frozen instructions again.

I hope I'm wrong, but it's better to check with this app.

Worth a try, but I can never count on how long a glitch will last. Is there an app that keeps a log of GPS info and accuracy? Seems like it would help with trial-and-error troubleshooting, since I wouldn't have to constantly keep my eyes on my phone instead of on the road, and I wouldn't have to stop at the side of the road and observe the GPS info.  It would be nice to compare a GPS log and Scenic’s recorded ride time stamps for issues.

Quote from Guido on 18.09.2025, 08:58

Interesting… but I’m still unclear why this is occurring - aren’t the raw locations are correct throughout, since my location displayed on the map is accurate? Maybe I don’t understand the difference between “logged” locations and ride recording data.

You should also see it "jump" during riding, but because it's only one location that's above the threshold distance, it would only be fore 1 second. After that second it will jump back.

Also not sure what increasing the route recalculation threshold distance would accomplish, since there is no route recalculation happening.

The name is a bit confusing in this context. It will only recalculate if locations received are further away from the route then threshold distance for a minimum of the threshold time. Since this is only one location (and locations are received every second), the recalculation doesn't take place, but the jump is logged.

Aside: I’m curious: when following a route, if I deviate from Scenic’s instructions, especially a “gentle” deviation like a highway exit which might not register right away, Scenic, I think, shows my location as on the route until I deviate a certain amount, then my location on the map “jumps” to the correct spot. Does this behavior demonstrate how Scenic “snaps” to the route until the threshold distance is reached?

Yes

Should we expect the recorded ride to indicate this “jump?”

Yes

I suppose heat could be the problem, but I’d be surprised. I have a “naked” bike, and my phone mount on the handlebars leaves the phone directly in the stream of moving air. Ambient temps on my recent rides have been in the high 60ºF (15C) range, with partly cloudy skies, so not always bright full sun.

I'm not sure if heat is a cause. Also not sure a wireless charger can cause this. Information on the internet about this is always anecdotal. In the end, the only way to really know is to measure and test.

Is there an app that keeps a log of GPS info and accuracy?

I found this one: https://apps.apple.com/mx/app/speedlap/id6749648704?l=en-GB Haven't tried it though. Not sure if it logs horizontal accuracy.

Not sure what you mean by #3, “location timestamp should not be older than 5 seconds.”

Each location that apps receive from the GPS receiver has a timestamp. Sometimes, the received location is "old". Scenic doesn't process locations if they are from 5 seconds ago or earlier. It's possible that the accuracy of your GPS receiver is still OK, but that iOS throttled back performance, making the GPS receiver give old locations for a while. This could even be caused by Scenic performance issues, or the combined performance of the apps you are running at the same time.

 

I asked ChatGPT what can influence GPS accuracy and/or performance:

📱 iPhone Hardware & Software Factors

 

• Antenna placement

  Covering the top of the iPhone with your hand, a case, or a mount can attenuate signals.

• Metal cases or accessories

  Can block or detune the GPS antenna.

• Wireless interference

  Although GPS runs at 1.5 GHz, strong nearby RF (e.g., cellular boosters, Wi-Fi routers, poorly shielded car chargers) may raise noise levels.

• Overheating

  Wireless charging or hot weather can make the iPhone throttle GPS and other sensors.

• Battery saver / Low Power Mode

  May reduce GPS polling frequency or disable background location.

• Software bugs

  Sometimes iOS updates or app permissions affect location performance.

• Compass calibration issues

  If the magnetometer is miscalibrated (due to magnets nearby or not enough motion for calibration), direction arrows in maps may feel “off.”

 

With this is mind... here are some other things you can try:

- Close all apps you are not using by swiping up in the app switcher.
- Before you start a ride, close Scenic completely and then re-open
- Download offline maps in Scenic (will prevent Scenic from needing to download map data while 'on the move', which takes performance and battery)

Quote from mattsz on 18.09.2025, 12:51

Quote from Guido on 18.09.2025, 08:58

I'm not sure if heat is a cause. Also not sure a wireless charger can cause this. Information on the internet about this is always anecdotal. In the end, the only way to really know is to measure and test.

The suggestion that heat may be a factor was yours, a couple of posts ago, which was why I mentioned it.  Wireless charging "issue?" Who knows? The evidence displayed in my recorded ride when I switched it off and on again looks damning... but it could be a just a coincidence.

Is there an app that keeps a log of GPS info and accuracy?

I found this one: https://apps.apple.com/mx/app/speedlap/id6749648704?l=en-GB Haven't tried it though. Not sure if it logs horizontal accuracy.

I don't see any apps that specifically mention logging of horizontal accuracy over time.

I have the free GPS Info app installed on my "user" iphone and my GPS-dedicated iphone... when I start the apps on both phones at the same time, they behave very similarly, with horizontal accuracy starting out at round 15m and settling in to around 5m over a minute or so... the numbers wander a bit, but they're very similar.  Does this suggest something about GPS accuracy issues?

Aside: interestingly, they both show a speed of between 0.1 m/s and 1.0 m/s, even though they're both at rest on the table.

Not sure what you mean by #3, “location timestamp should not be older than 5 seconds.”

Each location that apps receive from the GPS receiver has a timestamp. Sometimes, the received location is "old". Scenic doesn't process locations if they are from 5 seconds ago or earlier. It's possible that the accuracy of your GPS receiver is still OK, but that iOS throttled back performance, making the GPS receiver give old locations for a while. This could even be caused by Scenic performance issues, or the combined performance of the apps you are running at the same time.

See below...

I asked ChatGPT what can influence GPS accuracy and/or performance:

...

With this is mind... here are some other things you can try:

- Close all apps you are not using by swiping up in the app switcher.
- Before you start a ride, close Scenic completely and then re-open
- Download offline maps in Scenic (will prevent Scenic from needing to download map data while 'on the move', which takes performance and battery)

When navigating, I always have only Scenic open, no other apps running.  I usually open Scenic fresh before a ride, as I use my computer for planning.  I have offline maps downloaded - my "nav" phone has no sim card and no cellular data available.  I keep wifi, etc, all turned off, and airplane mode on.

One thing I could try is substituting phones... we have three SE's in the house: my nav phone, my regular phone, and my wife's phone.  Both of mine have Scenic installed.  Could be interesting to see if all three demonstrate the same problems.  Would that be useful data?

Only problem is, no more long rides planned for this season...

Quote from Guido on 18.09.2025, 13:02

The GPS Info app seems to indicate that GPS receiver is OK.

Trying a different phone could definitely shed some light on this. It could rule out or confirm if it's something with your GPS receiver. If not, then it's likely a performance issue with Scenic. I would have expected more feedback in that case, but you never know.

Quote from mattsz on 18.09.2025, 13:15

Quote from Guido on 18.09.2025, 13:02

The GPS Info app seems to indicate that GPS receiver is OK.

At the moment.  The symptoms seem to appear very intermittently.  right now, I've got my nav phone sitting outside in the bright sun, with the GPS Info app on the screen, watching the accuracy as it heats up.  No change yet... and it's getting pretty warm!

Next I'll see if placing it on the wireless charger shows any changes...

Trying a different phone could definitely shed some light on this. It could rule out or confirm if it's something with your GPS receiver. If not, then it's likely a performance issue with Scenic. I would have expected more feedback in that case, but you never know.

I have no idea when I'll be able to try the phone swap... but I'll definitely let you know!

Quote from mattsz on 19.09.2025, 07:08

A followup scenario, testing a different phone...

Admittedly, the circumstances are quite different.  I used my car, not my bike, to drive to a friend’s house yesterday... a 35-40 minute trip of about 22 miles. I decided to test my “personal” iPhone’s GPS interaction with Scenic, instead of using my dedicated navigation phone… so, different phone than I used for all of the above discussions. Wifi, bluetooth, and cellular data were all on, but Scenic was the only app running. I have offline maps installed for my area, and I don’t allow Scenic to access to cellular data at all.

I asked Scenic to guide me via a standard car route with “shortest” route preference, with no added stops or vias. I tapped the “Ride” button, then plugged my phone into my car to access wired CarPlay. The dashboard display came up as expected, with the “ride” already active and waiting for me to begin moving. I placed the phone on a dashboard shelf in the center console, which basically buries it beneath the climate controls and the dashboard screen. I ran into unexpected traffic on the way, so I deviated slightly, but Scenic recalculated as expected, and in fact it worked as expected the whole trip, with no obvious glitches or errors (but I wasn’t looking at the screen all the time). I saved the trip when I got to my destination.

On the return trip home, I created a new route the same way, choosing “home” as my destination. No surprise, Scenic provided directions to follow the exact same route, “in reverse.” This time, I didn’t plug the phone in, but instead placed it on my car’s wireless charging pad, which is located in the center console immediately below the shelf I mentioned earlier. So the phone was essentially in the same location in the car - about 3 inches lower than before, but otherwise buried beneath the same dashboard equipment in the same way. This time I couldn’t monitor the progress, since I wasn’t using CarPlay and I couldn’t see the phone’s screen. But when I got home, I saved the trip.

I suppose this whole experiment could be written of as anecdotal… nevertheless, comparing the “recorded rides” results of the two trips is eye-opening.

The first trip’s result is flawless. No long gaps in the record at all, and only two small “blips” which are actually spots where I deviated from Scenic’s route, and Scenic “snapped” my location to the route until it knew for sure I had deviated, then it followed along. So, expected behavior.

The record of the return trip is a hot mess. There’s a few small glitches, but many major gaps which show straight lines between points and therefore indicate, if I understand Guido’s explanation, inaccurate or unusable location information.

Here’s a couple of images. The differences in the trip recordings are difficult to indicate; zoomed in or out too far excludes detail. But here’s a side-by-side image - on the left is the accurate trip south, and on the right is the glitch-filled trip north. It’s difficult to see here, but the track in the map on the right is mostly straight lines which don’t follow the road:

The trip summaries that Scenic provides are revealing: when I enable the charting of speed or elevation, the colored graph along the bottom of the map includes gaps where the GPS position wasn’t recorded. Compare the first successful trip with the second glitchy one:

One additional interesting feature: the following glitch occurred on the return trip, during a brief moment when Scenic actually knew where I was - but look at the recorded track! On the right is the web-based map, zoomed in as far as possible; on the right is Scenic’s map display, also zoomed in all the way. Note the scale of the map; this is a stretch of about 100 feet that took just a few seconds to traverse…

The evidence against wireless charging may be circumstantial, but it appears damning.  Still unexplained, though, is why the problems were minimal when I first started using wireless charging a few years ago, and seem to have gotten worse over time…

Guido, let me know if you'd like me to send you links to these "rides"...

Quote from Guido on 19.09.2025, 08:44

Thanks @mattsz.

That sheds some light on the situation. BUT... we still not can conclude it's the wireless charger. Why? Because some CarPlay systems have an integrated GPS receiver. If your CarPlay system has one of those, then your iPhone will use that GPS receiver, and not the one that's built into your iPhone. What CarPlay system do you have (or car brand and model)? I'll try to find out if it has an integrated GPS receiver.

A good test would be to do the ride again, but this time do NOT connect to CarPlay and do NOT use the wireless charger. If that gives a good recorded ride (no big jumps) it's definitely the wireless charger.

I'm working on a very small app to log the raw location information. Once that's done, we should get a better idea on what's happening.

Quote from mattsz on 19.09.2025, 16:28

Quote from Guido on 19.09.2025, 08:44

Thanks @mattsz.

That sheds some light on the situation. BUT... we still not can conclude it's the wireless charger. Why? Because some CarPlay systems have an integrated GPS receiver. If your CarPlay system has one of those, then your iPhone will use that GPS receiver, and not the one that's built into your iPhone. What CarPlay system do you have (or car brand and model)? I'll try to find out if it has an integrated GPS receiver.

Interesting... I don't mind sharing that I own a 2021 Toyota RAV4 XLE, with plug-in-only (not wireless) carplay.  I did a couple of google searches, and the AI overview results offer conflicting information.  But the general consensus seems to be that only Toyotas that have premium audio systems, which includes built-in mapping, have GPS available.  I do not have a premium audio system.  But I'm still not sure, so maybe you or someone else who is better at googling (that would be just about anyone) can find out for sure...

A good test would be to do the ride again, but this time do NOT connect to CarPlay and do NOT use the wireless charger. If that gives a good recorded ride (no big jumps) it's definitely the wireless charger.

I had the chance to do that today... oh well, I'll give it a try first chance I get...

I'm working on a very small app to log the raw location information. Once that's done, we should get a better idea on what's happening.

👍