Major Altimeter-Barometer-Temperature Malfunction

Over the past several years, I have had a series of Forerunners (910XT, 920XT) and Fenixes (2, 3, 3HR, 5x) which have all developed total malfunction of altimeter-barometer-temperature. I seem to have been one of the few until the 3HR, on which many had similar problems. Just the other day I was thinking to myself that maybe this would not happen with the 5x, until mid-morning yesterday when suddenly while at work, the problem developed on my 5x. The clue is that the altitude suddenly went to approximately -65,000 feet. The barometric pressure showed no change. The temperature read 451 degrees. I tried recalibrating the altimeter, at which point the barometric pressure became bizarre and incompatible with life. So, I updated to the new beta firmware (4.21) with no change in these reading. I then soaked in soapy water (on the theory that the sensor port may be clogged; this has never worked for me). Then I did a hard reset. Following the hard reset, here are the numbers: altitude -68337, barometer 1013.2, temperature 561.

I realize that I may be the only person who has had this problem with every one of the devices. I wonder if there is something in the pool I use (salt water pool at Lifetime fitness) that degrades the sensors. I take impeccable care of the watch and rinse the sensor port under running fresh water after every workout. I'd rather not have these features on my watch than have these bizarrely wrong values and am not sure what to do at this point. I will call Garmin Monday and they will probably replace the device (hopefully). I love the functionality of the 5x and there is nothing out there that compares but I hate going through this repeatedly and am seriously considering switching platforms, though nothing out there appeals to the same degree.

I welcome suggestions.
  • Not all are defective... with bike-spinning-hydrobike-pool swim and aquagym, if you add the showers and spa mine is a combat F5X. I did have the malfunction and RMAed after 6 months. This is the second F5X then, brand new, 3 months and it's doing ok. The instrument is not necessarily defective and since it's exposed to the outer environment for obvious reasons, it is prone to suffer from the hardship of training types of all kinds.
    At the beginning, the lines of production are not yet tuned to solve manufacturing problems... waves subsequent to the initial release are more and more sturdy luckily.

    I never had this problem with the F3 but I did have it with 3 FR910XT in a row (20 days in ... then RMA... 3 times in a row so I sold the 4th for scrap value).
  • I just got a new replacement Fenix 5X for another unrelated issue and my new device has a faulty altimeter. Crazy thing is that I recently bought a vivoactive 3 and it's also experiencing similar issues. I feel like I'm experiencing the Fenix 3HR altimeter issue all over again in 2 different devices.
  • Same with me. My 4 month old 5x had a total failure of A-B-T. Just sent it back yesterday. I also had a failure of my 920xt earlier in the year. I guess I might be one of those unlucky people
  • I've just upgrade from a 3 HR to a 5. After 5 days the barometer is reading 4354.6mbar and my wrist is -51 degree C !!!
  • Over in the 5/5S forums its pretty easy to see that static electricity is causing our altimeter to go crazy. Lots and lots of issues.

    https://forums.garmin.com/forum/on-the-trail/wrist-worn/fenix-5-5s/155092-


  • As I've pointed out before, I think that there are multiple (or at least two) versions of the ABT problems. The one I have now had on multiple Forerunner and fenix units does not seem to be static related. I'm now on my third fenix 5X. All was fine until this morning when about three hours after a swim, the usual constellation occurred. The temperature, barometric pressure, and altitude all steadily went to values incompatible with life, while I watched. They are now frozen at the following values: altitude minus (-) 12132 feet; temperature 566 degrees Fahrenheit, barometer 5057.3. I've been trying to call Garmin....
  • My Fenix 5 doee the same thing sometimes . I will soon be on my 4th Fenix 5
  • Just off the phone with Garmin support. They will send a new, not refurbished, Fenix 5S overnight. This is my second (or is it third?) replacement for the Fenix 5S for altimeter issues. This time it was altimeter and temperature. Despite GPS and manual altimeter recalibration, my altimeter would read 65000+ shortly thereafter and my recorded rides would read 0 ft elevation or something equally inaccurate. The temperature has been reading 111-113 degrees (btw first support guy I talked to a few days prior tried to tell me this is just a reading that takes into account sunlight, ambient air, body heat, etc. Uh Nope). Support mentioned that watches manufactured around the same time (serial number) as mine had the highest number of similar issues. S/N 566039576
  • Over the past several years, I have had a series of Forerunners (910XT, 920XT) and Fenixes (2, 3, 3HR, 5x) which have all developed total malfunction of altimeter-barometer-temperature. I seem to have been one of the few until the 3HR, on which many had similar problems. Just the other day I was thinking to myself that maybe this would not happen with the 5x, until mid-morning yesterday when suddenly while at work, the problem developed on my 5x. The clue is that the altitude suddenly went to approximately -65,000 feet. The barometric pressure showed no change. The temperature read 451 degrees. I tried recalibrating the altimeter, at which point the barometric pressure became bizarre and incompatible with life. So, I updated to the new beta firmware (4.21) with no change in these reading. I then soaked in soapy water (on the theory that the sensor port may be clogged; this has never worked for me). Then I did a hard reset. Following the hard reset, here are the numbers: altitude -68337, barometer 1013.2, temperature 561.

    I realize that I may be the only person who has had this problem with every one of the devices. I wonder if there is something in the pool I use (salt water pool at Lifetime fitness) that degrades the sensors. I take impeccable care of the watch and rinse the sensor port under running fresh water after every workout. I'd rather not have these features on my watch than have these bizarrely wrong values and am not sure what to do at this point. I will call Garmin Monday and they will probably replace the device (hopefully). I love the functionality of the 5x and there is nothing out there that compares but I hate going through this repeatedly and am seriously considering switching platforms, though nothing out there appeals to the same degree.

    I welcome suggestions.



    I have had the exact same issues for the past 2 years. I have worked through approximately 5 watches .. in the Fenix range. My first being Fenix 3. Then I soon moved to the Fenix 5 range but all have failed on the Temp/ Barometer and Altitude sensor. For all watches to fail is crazy and my newest Fenix 5s plus was purchased on 31st August.. Sensor seems to have failed on the 13th October. I Swim five days a week . I pray it is not the pool water. My pool water has no salt. I am now wondering if it is shampoo / washing products that is causing failure. A possible certain ingredient in some washing products?. I wear my watch 24/7 and only remove for charging . I have replacement watch being sent to me tomorrow . The only other product I have used when wearing my watch is a descaling spray in my shower enclosure .. and I de-scale every two weeks normally when I shower on Saturday mornings straight after a run. . so .. maybe this product kills the sensor.. I will have to try some process of elimination. If the watch is failing simply from pool water, then it is not fit for purpose and Garmin will seriously need to sort this out. My sensors are failing within a few months so I seem to be forever returning the watch for new, but losing or my personal records etc in the process.
  • I know this is an older post, but I am waiting on my third Fenix 5S to arrive. I too have had my first two watches develop this issue. The temperature is stuck at 573 degrees and the elevation was stuck at some ridiculous amount (I live in Florida, no elevation), but I manually entered elevation in an attempt to calibrate and now it's stuck on that setting. I remove my watch when I shower (that's when I charge it) and I swim several days a week. I don't find anything visible in that sensor hole. I think this is an electronics/software issue and not a "plugged hole" issue. (just my non-educated vote). I do love the watch, and hope I don't continue to be one of the ones experiencing this issue.