Anyone STILL having heart rate accuracy issues with their Fenix 6?

Hi all,

Super frustrated, but I am still having issues with my Fenix 6S and heart rate accuracy even with the 4.20 software update. I'm wondering if it's just me or what the deal is? I had a 5S Plus before this and had no issues doing the same activities so I really don't think it's user error. My heart rate hardly reads over 110 during really vigorous exercise when my heart rate is closer to 160+. I have tried wearing on the inside of my wrist, tried my other wrist with no luck. It consistently reads 80-110 bpm the whole time. I wouldn't have bothered to upgrade if I knew this was going to be an issue. I know that wearing a chest strap is the most accurate, but I don't like to have to wear it for all of my work outs and my old Fenix was totally fine as well as my apple watch before that. Any suggestions? 

  • One more frustrated and already former Garmin user. 

    I've been using the watch for 3 weeks, struggling to find the reasons for the poor HR reading in "Cardio" and "Others" activities... HR works fine while running, but as some people already said here, it might be related to the algorithm or the readings.

    But that's not HR, there are many bugs and bad UX design, something you wouldn't expect from a respected and niche brand.

    Anyway, the frustration I got reading this thread was bigger than the frustration i got form the poor readings... It's absolutely nonsense the way Garmin is dealing with this problem and its customers. It is a FACT that the older versions and watches the WHR worked, even if not perfectly. In F6, WHR simple doesn't work as branded.

    And there's this philipshambrook here - Garmin is spending their budget in this guy to entertain we all here, instead of hiring programmers to solve the many issues we have.

    Absolutely unacceptable for a product within this price range.   

  • There are two different modes: Broadcast Mode that sends the 24/7 data

    Have you ever watched the LEDs? If they change from flickering to continuous lighting, the watch no longer uses the 24/7 mode.

    The built-in Garmin HR widget also leaves 24/7 mode. If you want to know which HR your watch records in 24/7 mode, I recommend this Heartrate widget. It leaves the watch in 24/7 mode.

  • There is definitely something funky going on with the OHR on this watch.

    I have a Fenix 5x as well, which I NEVER had trouble with on the OHR.  It's too slow to read well during activities, but other than response time it's fine.

    The 6x, on the other hand, records impossibly-high numbers on average once or twice a day.  Like 192 this morning, which is flat-out nonsense; it persisted for a while too, then went away and is normal.

    It's gotta be a software thing since I also wore the watch (and no chest strap) on a 4-hour+ hike the other day, and the OHR behaved just fine.  It also behaves fine most of the time otherwise.  But when it goes nuts, well, it really does.

    Here's hoping Garmin can figure out what's up with that and fix it, because it's the one serious wart I have with this watch.  Otherwise, everything is working very well.

  • Do you have to keep this widget open and viewing?  Or will just having this widget in the background put the hr on 24/7?

  • You have to open the widget. It shows the current heart rate recorded by the watch without leaving 24/7 mode.

  • It is a FACT that the older versions and watches the WHR worked, even if not perfectly.

    But surely this is the same argument you're putting forward here?  WHR either works accurately and reliably or it's not working

    as branded

    What degree of imperfection are you prepared to accept? Am I missing something? Are you suggesting that despite not working perfectly that WHR was still acceptable for you with older watches?

    It most certainly 

    is a FACT that the older versions and watches the WHR worked,

    Because it did work so it is indeed a fact. It just did not work very well. I was one of those decrying the accuracy and reliability of WHR on the 935 when I first got one. If you think it's bad on the F6 spend some time reviewing some of the posts about WHR shortly after the 935 and possibly the other watches around that era with early versions of wrist heart rate. Here's some to start with:

    There's nothing new being said here that hasn't already been said since Garmin started putting optical heart rate on watches. However, IMVHO, it has got better and works for more people more often but optical heart rate monitoring will never work for everybody every time.  

    As people keep repeatedly saying, there's no point having WHR if it doesn't work perfectly (irrespective of the degree of imperfection). That's why I usually wear a strap if I want to be certain of accurate and reliable results during activities, which strangely enough is what Garmin and Polar recommend too. And I am comfortable that 24/7 works well enough for me not to have any concerns about it's accuracy and reliability.

    YMMV in which case contact Garmin Support and help them make it work better for you.


    I don't work for Garmin. I'm actually unemployed while I finish my PhD thesis. Yay! Two weeks to submission Slight smile

  • During a 70 minute hike yesterday there was almost no time when my 6X WHR matched the values from my wetted TickR strap. I could not check the TickR values whilst hiking, but I know the 6X was not raising heart rate for the uphill sections or lowering it as pace/ascent reduced. A very disappointing result. Mostly the values are plausible, taken in isolation, which might make them credible, but they are almost entirely wrong.

    6X is green. TickR is red. Only 4 BPM difference in the average, but that might give a false sense of accuracy when you look at the reality of the graphs. In particular, notice towards the end when both WHR and TickR rise as I climb, but back on the flat to the finish the WHR remains elevated while the TickR correctly tracks my reduced effort.

    By the way, this was a hands free hike - no walking poles, no rucksack straps to hold on to, no dog leads. Just hands loose by my side.

  • Another hike today, this time 80 minutes.

    6X + WHR on left wrist in green

    5X+ + WHR on right wrist in blue

    3HR & V800 at waist with TickR in red

    In general the results are there or thereabouts, but in the later stages the 6X is peaking repeatedly above reality for no reason at all. My hands were empty and relaxed. Pace was steady. The watches with WHR were equally snug, without being too tight.

    Overall the 6X showed average HR +3 BPM above the other devices. The 5X+ average was within a gnat's fart of the TickR. There is no logic to it, not for Garmin's latest and greatest creation. It should do better than this. It should not be worse then the 5X+.

  • The 5x sensor design is better.  LED's surrounding the sensor in a triangle, and 3 of them. 

  • One thing just came to mind while reading on 6 series OHR issues.

    6 series introduced new sensor - and before we all burry it in comparisson with series 5 - could it be attributed to some  software changes between 2 generations.

    For example - Garmin Pay (series 6 "thingy") uses OHR sensor  (proximity) to check f the watch was removed from the wrist, as a safety measure. In layman terms - that could steal some "processing" time from its basic functionality which is OHR.

    So if there is anything else that could interfere with sensor "processing" time - how about  disable or not use that feature first and see if sensor works better.

    I have OCD for this with all my devices, and usually disable bunch of processes both on my Windows laptop and Android phone, which make them work faster (no lag).

    So wondering - if it makes sense that people with the  OHR sensor issue make a log containing sw, installed apps, used features (like Garmin Pay) and someone could run comparison check to see if there are any overlaps that could point to software background of these problems.

    My point is that CIQ environment is closed-source and still relatively young..