Just about every single one of my runs these days has an elevation line like this. The yellow line is the FR935's barometric altimeter elevation reading. The blue line is the corrected GPS elevation line for the same run. This is pretty representative of the lines I see on all my runs this winter. And it's totally messing up my elevation gain numbers. On this run it's 518ft vs 192ft. I've had some runs where the BA's total is 5 or 6 times the GPS elevation's total gain. Any ideas what is going on? Has my unit's BA decided to crap out or is this expected behavior in the winter time when my wrist is covered by a layer or two of sleeve. ciq.forums.garmin.com/.../1296310.png
Same here, a slight drift is normal but there has to be some kind of "hardware" issue in your case. Maybe as simple as some debris blocking the sensor ?
Is the error correlated with the temperature reading of the watch?
If you turn on the Ambient Pressure datafield (not Barometric Pressure!), how much does the reading change during a run? (If it is a problem with the ambient pressure sensor, I would expect the Ambient Pressure reading to change 15-20 millibar during the run in your picture.)
Do you use synthetic clothing which can cause static electricity? Several F5 and F3HR users have reported that they have problems with the ambient pressure sensor when they wear synthetic clothing. But if they submerge the watch in soap water for 30 minutes, the problem goes away for a few days. F3 which has another pressure sensor than F3HR and F5, does not have this problem. I don't know if your 935 has the same sensor as some of those watches.
There's no visible debri. I soaked the watch in warm soapy water for 5 minutes the other night. That doesn't seem to have helped. Here's yesterday's run. Same basic shape that I get on every run. I'm not sure when this began exactly. Maybe began with winter cold temps and more clothing worn? Or a firmware update? Or a new location? (I moved in september, though only a couple miles away.) I've had the watch for 9 mo and know it hasn't always been like this.
AllanOlesen67 I'm not sure if it's correlated w/temperature. It IS cold outside these days, typically 5-20 degrees F. And I certainly don't bring the watch outside to sit prior to starting my run. Besides, it's buried under usually two layers of sleeve so I would think that it's not getting THAT cold. Usually a synthetic material with a merino wool 2nd layer.ciq.forums.garmin.com/.../1297310.png
AllanOlesen67 I'm not sure if it's correlated w/temperature. It IS cold outside these days, typically 5-20 degrees F. And I certainly don't bring the watch outside to sit prior to starting my run. Besides, it's buried under usually two layers of sleeve so I would think that it's not getting THAT cold. Usually a synthetic material with a merino wool 2nd layer.
Well, the standard procedure in any problem solving of this kind is: Try to isolate the possible causes, so you don't change more than one possible cause at the time.
So in your case, try only changing the temperature of the watch. It could be as simple as:
Wear the watch for some time indoor without any long sleeves. The watch will be heated by your body heat, and there will be no synthetic materials to create static electricity.
Write down the watch's readings of temperature, barometric pressure, ambient pressure and altitude. (Make a data screen in a non-GPS activity so the watch doesn't try to autocalibrate the altimeter when it gets a GPS fix).
At the same time, get the pressure from a nearby weather station. (It will not matter if the weather station reports pressure in true ambient pressure or equivalent pressure at sea level.)
Put the watch on a table for 30 minutes so it cools down.
Write down the watch's readings of temperature, barometric pressure, ambient pressure and altitude.
Check the local weather station again to see if pressure has changed in the mean time.
Compare!
If you change the temperature of the watch this way, and the ambient pressure changes significantly (and differently from the weather station), you probably have a sensor problem.
You mentioned submerging the watch in soap water for 5 minutes. The other persons who have reported success with the the soap water treatment have submerged it for 30 minutes.
A few users claim to have solved their pressure sensor problems by uninstalling custom watch faces. This sounds quite crazy, but it would not be the first ever example of a crazy bug in software.
I called Garmin Support and he acknowledged from looking at a few of my activities in GC that there does appear to be a problem. He found another open case that is the same issue and added me to it. I asked how long it's been open and he claimed not to be able to see that info, but shared that there were 4 others on the case so that it didn't seem like a widespread issue. We'll see if anything comes of it.
Since my software update to 7.60 my elevation doesn’t work at all. I tried a factory reset, soaking in warm water, recalibration etc. I’ll be calling the support number tomorrow.
I called Garmin Support and he acknowledged from looking at a few of my activities in GC that there does appear to be a problem. He found another open case that is the same issue and added me to it. I asked how long it's been open and he claimed not to be able to see that info, but shared that there were 4 others on the case so that it didn't seem like a widespread issue. We'll see if anything comes of it.
I've also been onto Garmin connect and added to a "known" case. I was asked to send the contents of my Garmin folder which I have done.
My issue is I am seeing incorrect elevations stat, ie playing field hockey on an flat artificial surface I see 61m elevation gain and 73m elevation loss!
Looking back this was working better in June 2017 on sware version 4.10 when I only saw a 10m elevation gain for a hockey game and also a flat 5km park run May 2017 on firmware v3.30 with a 6m elevation gain
I looked back as well and found that it began around October for me. Not sure about firmware versions. But Oct is about when the temp starts dropping here. I'm in Michigan. So I suspect it could be temperature related.
