Wrong total distance for activities longer than 167.76 km [Bug 10]

[Przekątny]

User data limits of the eTrex SE are specified here.

The data provided concerns something else, concerns the recording of current activity and not the display.
This information is missing:
Track graph 20,000 points, 250 routes saved in gpx format, 300 activities saved in fit format.

It is a pity that the files sent are not the original files created on the device, the original file may contain
statistics records that lower the distance.

[JungleJim]

You wrote 176.76 km multiple times, but the screenshots say 167.76 or 167.77.
It could be a software error. The maximum value of a 24 bits unsigned integer is 16,777,215; if the unit used is the centimetre this corresponds with a maximum value of 167,772 m or 167.77 km... This is way too much of a coincidence.

This could indeed be a likely explanation. The FIT format specifies activity session total distance as an unsigned 32 bits integer value in meters with scale 100, which means that the stored value is divided by 100 to get the distance in meters. So if you take the max of a 24 bit unsigned integer (16,777,215), divide this by 100 you get 167,772.15 meters, which is 167.77 kilometers with two decimals. So maybe the eTrex SE uses a 24 bit integer to display the total activity distance?

Sibstr, can you also share the original FIT files of the activities you recorded? Then it is possible to check what data is actually stored.

[javawa]

It is a pity that the files sent are not the original files created on the device, the original file may contain
statistics records that lower the distance.

Yes, they certainly do contain statistics records. That's why Connect also shows the incorrect distance.

[Przekątny]

A test for displaying the correct distance can be to convert the activity into a direct route in Base Camp,
the route will retain its current shape and distance.

Then check whether the Etrex SE displays a distance of over 300 km or whether it will display a distance of 167.77.

[javawa]

Th eTrex SE converts routes to courses, with a limit of 200 points points (according to the info on the Garmin website).
So no support for direct routes… (even if it would support them the limit would be 250 points, like every outdoor Garmin)

[Przekątny]

The format the device processes does not matter, what matters is whether the total distance will be displayed based on the route, unlike the track saved in the gpx or fit file.

During processing, the number of points can be limited to 199 without losing the shape of the track, the distance may change but it will still be over 300 km.

[Sibstr]

176.77 Km is the maximum that the eTrex SE shows me for distance in all situations. For example, I'm driving and I have two values live ​​displayed on the display, speed and distance. While the speed changes throughout the journey, the distance always stops at 176.77 Km. And than I see the same distance in the activity in GPS, in Garmin Connect, just everywhere.
Attached are the original FIT files.

Spoiler

FIT.zip

[JungleJim]

176.77 Km is the maximum that the eTrex SE shows me for distance in all situations. For example, I'm driving and I have two values live ​​displayed on the display, speed and distance. While the speed changes throughout the journey, the distance always stops at 176.77 Km. And than I see the same distance in the activity in GPS, in Garmin Connect, just everywhere.
Attached are the original FIT files.

Spoiler

FIT.zip

Thanks for sharing the FIT files. I took a look at them with fitefileviewer.com. Definitely looks like a bug in the eTrex SE firmware to me. The FIT file contains Record messages that are similar to track points in a GPX track file. The distance reported in the record messages in the FIT file simply maxes out at 167.76 or 167.77 km even though there are more records present.

There is also a Session message in the FIT file, this corresponds to a summary of the activity. The distance reported in the session message is also the same as the maxed out value in the Record messages.

Here are two example screenshots from one of the recorded activities (the displayed distance is in meters).

Spoiler

Screenshot 2025-01-01 at 16.50.03.png

Screenshot 2025-01-01 at 16.50.15.png

In the first screenshot you see the distance increasing (4th column) up to 167,759.86 after which it stays at that value even though the lat/lon keeps changing (2nd and 3rd columns). The second screenshot shows the total distance as 167,759.86 as well. Afaik this value is used by Garmin Connect (and not the distance in the individual track points).

So I'd definitely report this to Garmin support with the evidence of the FIT files.

[Przekątny]

In my opinion, the file 2024-09-14 08.32.29.fit distance is registered correctly (360 km),
the value <gpxtrkx:Distance>167768.328125</gpxtrkx:Distance> (~168 km) is entered in TrackStatsExtension.

After changing the value to another (any) in the Base Camp statistics, the entered value is displayed,
after deleting the sequence in the Base Camp statistics field, the value 360 ​​km is displayed.

Will the file modified in this way display the total distance in Etrex Se?
It should be checked.

[JungleJim]

In my opinion, the file 2024-09-14 08.32.29.fit distance is registered correctly (360 km),

How do you come to this conclusion? Open the FIT file in fitfileviewer.com and check the Record and Session messages and you will see that the distance registered there maxes out at 167,759.86 meters.

the value <gpxtrkx:Distance>167768.328125</gpxtrkx:Distance> (~168 km) is entered in TrackStatsExtension.

The GPX format and TrackStatsExtension is not relevant in this case I think, as the eTrex SE (and many other devices) use the FIT file format for recording activities. Opening a recorded activity will show the info from the FIT file. Saving in GPX format is a conversion and a derivative from this FIT file.

After changing the value to another (any) in the Base Camp statistics, the entered value is displayed,
after deleting the sequence in the Base Camp statistics field, the value 360 ​​km is displayed.

Will the file modified in this way display the total distance in Etrex Se?
It should be checked.

I'm not sure what this will prove. When modifying data of the GPX file in Basecamp, Basecamp will recalculate the statistics based on the track points. This will result in a correct distance because the lat/lon coordinates in the FIT files seem to be correct. But the distance recorded in the FIT file is incorrect, and this is the source the eTrex SE most likely uses and Connect for sure uses.