Altimeter issues since SW version 25.00

Since the update to Software Version v25.00 (3ca0dea) on my fenix 5, the altimeter is not accurate in several activities. Not accurate being hundreds of meters above the actual altitude. I've rebooted the watch and re-calibrated the Altimeter under 'Settings > Sensors and Accessories > Altimeter > Calibrate', where I've chosen the GPS calibration option. Auto Calibrate is on and elevation is measured in meters. I notice that since the update the GPS circle, when starting an activity, became yellow instead of green (like it was before SW version 25.00).

0 carleson over 2 years ago

The circle still goes green on mine, with v25.00. This is important detail you included that it stops at yellow. With the autocalibration on, that means it uses the GPS to calculate the starting elevation and at yellow circle it doesn't have a full gps lock yet and thus not a fully resolved GPS altitude. Is the rest of the graph correct - just offset by hundreds of meters? If so then the altimeter/barometer are working but then the initial value from GPS is not good. Wait as long as needed for the circle to go green and see that helps. Maybe even longer - I remember on older watches we could see the gps calculated "accuracy" and it would get 3d satellite lock at 100 meters (?) but then if you continued to wait it would get to 10-15 m. (this is horizontal accuracy, not the elevation).

0 8033005 over 2 years ago in reply to carleson

Ok, thank for the fast reply, I’ll try again tomorrow and get back to you. I hope it is solved by waiting until the circle is green. Weird thing though is that before v25.00 is was almost immediately green and I’m running the same routes for 90% of the time. Nevertheless thanks and I’ll let you know

0 8033005 over 2 years ago in reply to carleson

Hi, I’ve tested this and still no luck. Even when waiting for over 10minutes before starting an activity, the circle stays yellow. The word ‘GPS’, does turn green. So I’m confused. It would be too much of a coincidence that my GPS got broken from the moment I updated to software version 25. Is there an easy way to go back to version 24? In that way, I can check if the GPS does run fine again. Thanks

0 tralphs over 2 years ago

Try turning off auto calibrate and set it to altimeter rather than barometer /auto.
I think that it is better to calibrate the altitude manually and use the watch as an altimeter rather than barometer.

0 8033005 over 2 years ago in reply to tralphs

Hi, thanks for the reply! In the settings under ‘barometer’, I’ve turned ‘watch mode’ to ‘Altimeter’ instead of ‘Auto’. I think that’s what you mean. I’ve set Auto Calibrate to ‘Off’ under ‘altimeter’ as well. I’ll try tomorrow and let you know if that helps. Thanks!

0 8033005 over 2 years ago in reply to tralphs

I’ve tried several runs with what you suggested and it did not work.

In the meantime I’ve deleted the watch from my account, performed a reset to factory defaults and re-added the watch.

The result was that GPS and the circle of the watch is becoming green right when I start an activity, so that’s sorted.

For 2 runs the altitude was correct (2 meters difference for the same route, but ok).

Then the fluctuations started again, today I did a run of 5km with 20 meters of ascent,

but it shows 70m of ascent.

When I look at the altimeter for the past 4 hours it dropped to -262m and got back to 84m (whet the effective height above sea level is at my home location).