Altimeter Fenix 5

But what never supported static charge theory, was the fact, that every time I reset device to factory setting (before claimed), nonsense number were immediately exchanged to the right (close to the right) ones. Which tends more to software issue - hopefully Garmin will find (or found with 8.00) a solution.

Think about what happens when the watch is sometimes measuring wrong ambient pressure due to static electricity. The auto switch between Barometer Mode and Altimeter Mode will try to make sense out of the changed ambient pressure, and as a result both altitude and barometric pressure will be thrown off course. Then the ambient pressure reverts to the correct value, but the damage to the altimeter and barometer calibration is already done, so now the watch will still have a wrong barometric pressure and altitude. Then, when you reset the watch, the Barometric Pressure gets reset to a standard value.

So your proof is not a proof.

Hi everybody,
during the last weeks I was reading and learning in this and other threads about this issue which also affects to me.
Now I would like to share with you my experience.
I am the more or less happy owner of the third Fenix 5 (1st and 2nd went back to Garmin because of crude altimeter failures: -15.000 to +20.000)
Now, with the 3rd one I am happier. But not completely.
Its somehow clear to me that I can not expect from a wrist-gadget the accuracy of a laboratory pressure sensor, but a kind of Consistency in the measurements would be nice to have.

I started two days ago to make home made data collection of the ambient pressure (not barometric) measured with:
- Fenix 5 (I created an extra data field in an activity to be able to read this value)
- iPhone 6s (installed app. Bar-o-meter to be able to read this value)
- Oregon Scientific Weather station (not decimal values)

You can find attached the results.


After these two days here are my first statements:
- iPhone and Weather station are very near from each other. With no exception.
- Fenix 5 and iPhone have differences from -1,5 mbar to +3,5mbar. Not really consistent.

I also include an evolution of the weather conditions in my city to compare.

Now to my question. Is this what I should expect from the Fenix?
Should it behave more consistent/accurate?

Thank you for your time.

Was the temperature of your watch the same all the time?

This ought not to matter, but in other threads some F5 owners have reported that they can change the ambient pressure reading of their watch by several millibar by moving it to a warmer or colder place.

(On my F3, I can't move the ambient pressure more than 0.2-0.3 millibar with a 20 °C temperature change.)

Was the temperature of your watch the same all the time?

This ought not to matter, but in other threads some F5 owners have reported that they can change the ambient pressure reading of their watch by several millibar by moving it to a warmer or colder place.

(On my F3, I can't move the ambient pressure more than 0.2-0.3 millibar with a 20 °C temperature change.)

I had the watch on my wrist all the time.
I can not tell the ambient temp fluctuation impact, but these days the temp is quite mild in Stuttgart. 15°C Outside / 23°C at home would I say.

But even though the temp plays a role... this oscilations in comparison to the other two sources make me mistrust the Fenix sensor.
Am I expecting too much?

Saying this problem is due to static electricity or the clothes you're wearing is a fine explanation but it's unacceptable for this to happen. You shouldn't have to choose your clothes for the day based on what will or will not cause problems with your watch. No other manufacturer has this issue that I'm aware of and I don't expect to center my day around coddling my altimeter watch.

I had a perfectly fine working Fenix 5 for 11 months and then the altimeter began behaving erratically. The first thing I noticed was starting a run at 11,000' and finishing at 1,000'. That's leaving from my car and returning to the same spot. My elevation is actually about 8,500'. I recalibrated the altimeter and assumed everything was fine. A few weeks later I noticed I was sitting at 35,000' in my living room.

I cleaned the port and ended up with a factory reset to rule out any issues.

Garmin's email support is supremely slow, probably due to dealing with all of these altimeter issues, and while awaiting a response at one point during a run my altitude dropped to -101,400' below sea level.

Garmin set up an exchange for me and I received a refurbished Fenix 5.

After spending the required time setting up this new watch, I woke up the next morning to find my altitude at 37,000'. This is on a watch I've had for less than 24 hours so I was pretty frustrated.

I called Garmin this morning to chat about it. He tried to assure me this is a rare case whereupon I interrupted him and told him about the 18 pages of people with the exact same issue on Garmin's own website, not to mention the rest of the internet..

The representative then tried to assure me the watch would correct to the right altitude over time. At this point my watch was saying 57,000'. I explained this was unacceptable and it's made the watch completely useless. Even when I calibrate using the GPS it pulls the correct altitude of 8,465' and when I click OK to accept that it only drops to 47,000'. 20 minutes later my watch says 46,427'.

Using the watch for navigating in the mountains is useless without showing the correct altitude. Thankfully with trail running I can have Strava correct the altitude when it's imported.

I was put on hold while the representative checked with his team. He told me they've been working on a new batch of Fenix 5 watches that have specifically been repaired with this issue in my. They should have been ready a couple of weeks ago so he said it sounds like they're close to shipping. He put my name on the list of recipients for one of these watches and I'll have to live with a non-functioning watch until then.

If you have altimeter/barometer issues, mention this information to Garim and be sure to ask for a watch that has been fixed for this specific issue. Otherwise it's likely you'll end up with a watch that has the same problem you're trying to fix.

Don't adjust your wardrobe or your daily routine around your watch. It should work in every situation. Otherwise what's the point in spending $600 for something you have to baby?

I completely agree that static electricity is the problem and have been saying so for months now. I even lost 2 Fenix 5 LCDs due to an extremely static environment. Its so easy to see that static is causing both my LCD failure and altimeter problems.

I had the watch on my wrist all the time.
I can not tell the ambient temp fluctuation impact, but these days the temp is quite mild in Stuttgart. 15°C Outside / 23°C at home would I say.

You could test if temperature affects your ambient pressure measurement. Better than guessing.

plays a role... this oscilations in comparison to the other two sources make me mistrust the Fenix sensor.
Am I expecting too much?

To me it looks like you are worried about the wrong aspect of the reliability of this sensor.

The barometric altimeter is put into the watch to give you good relative altitude measurements over a few hours. If you use it for altitude measurement over several days, you will inevitably get altitude drift because the ambient pressure around you is changing. This drift will be many times larger than the small errors you have documented, so you will need to recalibrate the altitude calculation several times during that period anyway.

So I don't really see the purpose of testing the reliability of your pressure sensor over several days. What matters is the reliability over a few hours - which you have not tested. As I wrote earlier, your ambient pressure measurement may be sensible to temperature variations. That can affect the reliability over a few hours, so that can be a real problem. But you seem reluctant to test that, which leaves me a bit baffled.

Since the fenix 3 HR too had this problem (quite a big thread for it too) and since I've had a defective device myself, I'm fairly certain it has absolutely nothing to do with static.

It is pure and simple a faulty hardware which Garmin won't acknowledge.

Many people have tried many different fixes. Many thought to have found a pattern for this erratic behavior. None has succeeded... So, no. It is not static, believe me.

And apparently Garmin has not learnt from its mistakes, since the fenix 5 series suffers from this very same problem.

You could test if temperature affects your ambient pressure measurement. Better than guessing.

T 31,1°C -> 970,6 mbar
T -4,7°C -> 968,8 mbar

What I meant with my "guessing" is that during the 2 days the temp could not have oscillated in such a big way as the watch was always on my wrist and the outside temp was quite constant.

The barometric altimeter is put into the watch to give you good relative altitude measurements over a few hours. If you use it for altitude measurement over several days, you will inevitably get altitude drift because the ambient pressure around you is changing. This drift will be many times larger than the small errors you have documented, so you will need to recalibrate the altitude calculation several times during that period anyway.

So I don't really see the purpose of testing the reliability of your pressure sensor over several days. What matters is the reliability over a few hours - which you have not tested. As I wrote earlier, your ambient pressure measurement may be sensible to temperature variations. That can affect the reliability over a few hours, so that can be a real problem. But you seem reluctant to test that, which leaves me a bit baffled.

May be my english is not good enough and i didn't explain it correctly. Over these two days I see a reliable trend. Macro. The reliability over a few hours is exactly what bothers me.

For example (you can read all hourly values on the graph I posted before):

10th April
between 11:00 h and 13:00 the difference to iPhone drifts from +3,6 to +0,9
between 18:00 h and 20:00 the difference to iPhone drifts from -1,1 to +2,1

11th April
between 13:00 h and 15:00 the difference to iPhone drifts from +2,2 to +0,2

For example (you can read all hourly values on the graph I posted before):

Yes, I can. I did not read your post closely enough and somehow thought that you had one data point for every day over some weeks. Sorry.

I agree that this hourly variation is so large that it will affect the usefulness of the altimeter.