Is my Fenix 5 faulty?

PY1974 over 7 years ago

I've had my Fenix 5 for approx 3 months now, upgrading from a Fenix 3. All seemed well until the last couple of weeks when I've noticed differences in elevation and now distance compared to other people doing the same races as me. Yesterday I ran a cross country race which I won, however, comparing my track to everyone else I am between .3 and .4 miles short, from the below link you can see on lap 4 it appears I took a shortcut which I didn't, but assume this accounts for some of the distance difference, fortunately lots of marshals on course to verify I didn't if anyone queried this. https://www.strava.com/activities/1281966408 The route was fairly well covered with trees but I would have thought this would have caused an issue on all laps and not just the final lap.

I'm on v6.0, checked altitude settings last night and these were about 80 feet out, re-calibrated by GPS and came in close to what reading on phone app said. Plan to do a GPS soak test tonight and see how it goes during training runs during the week and compare against others on next Sundays race, anything else anyone could suggest to confirm the watch is not developing a fault?

Thanks

0 mcalista over 7 years ago

Actually, that looks pretty normal.

I note from the satellite view that it is a forested area. The number of GPS satellites available in the observable horizon changes continuously as they move through their orbits, but if a time of low satellites is combined with tree cover, then this can lead to the number of visible satellites dropping below the minimum, and the watch missing a GPS fix for a short time. The watch and mapping algorithms are normally pretty good at filling in the blanks, but in this case they have joined the dots in a straight line, leading to a plot "cutting the corner". I am sure if you looked at a number of people's GPS plots from the same event, you will see quite a few cut the corner on a lap or two.

0 PY1974 over 7 years ago

Thanks mcalista, yes this is quite a heavy forested area so accept tracks won't be spot on, and looking at other peoples tracks in the same race none are the same for all 4 laps which is to be expected but don't understand the difference in distance, no one else has anything outside of 5.3 and 5.4 where as I got 5.01. I'll try the gps soak tonight.

0 mcalista over 7 years ago

Generally the GPS plot cutting a right angle corner won't make a huge difference. But the timing of the particular cut you experienced coincided with an almost hairpin corner, so some lesser assumed distance.

0 Former Member over 7 years ago

What distance is it showing in Garmin Connect?

0 PY1974 over 7 years ago

@bcalvanese Garmin connect shows as 5.01 miles - https://connect.garmin.com/modern/activity/2339964472