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? 

  • Garmin posted a comment in the Sensor Hub Beta v2.53 thread that the heart rate issue is being worked on and they will release an update specific to that issue as soon as they can.

    See here: Comment by odsweng

  • Pre 4.20 read low for reasonable effort, post 4.20 it reads 240bpm when I’m commuting at 18kph on my Brompton. I’m just going to use my external HRM-Tri for all recorded activity until this is fixed and use my Fenix 5 for all resting hr data

  • During hiking with my 6 Saphire today the average HR detected from the optical sensor was 91 bpm, which is also way too low. I'll also wait for a software fix. My Vivoactive 3 was much more accurate.

  • I have the opposite problem. When I hop on the elliptical, the watch tells me my hr is 190 for the first 10min or so and then gradually falls down to reasonable 130-140. For those wondering what's my point, my resting hr is 47 and chest strap puts my hr at 115 for those 10min of warming up. 190bpm is calling 911 and rushing me to emergency territory. The watch is a joke really - completely useless HR measurements.

    And yes, i've already tried 2 other Sapphire 6x watches purchased from different retailers all with similar results on 4+ firmware

  • yes - very frustrated, I had to stopped 3 times to move my 6x pro this morning - either ridiculously low - 60 bpm - or high - >150bpm  when I should be around 140. I found it really depends on the position on the wrist, but it's too too too sensitive! after update I could connect my garmin pod, but after turining off/on during the activity this morning I was not being able to reconnect it again. for 700 euros I was expecting much much more

  • Hi, 

    I also got a Series 6 Pro Sapphire this week and am very disappointed in the HR sensor. I moved from fitbit to Garmin and while the app and the watch are awesome, the HR sensor is extremely unsettling. I had 3 workouts so far, 2 of them mainly cardio. The first one seemed only clumsy, with average HR pretty close to what i expected, and a somewhat delayed instant HR read. The second workout I had to stop repeatedly just to see what's wrong. I could barely breath, my heart was punding and the watch would show a HR of 87.. Overall average of 87bpm for a pure cardio workout of 40 minutes. During the afterburn the watch would show instant HR of 110bpm, which was real.

    It seems that the HR is pretty accurate during the day and in rest conditions. But when I start to move, be it a simple indoors cardio, run up the stairs or bike run, it somehow fails to keep up with the actual heart rate and gets stuck showing totally bogus data. I even stopped to count my pulse and I got a 112bpm when the device was showing 83bpm.

    Any news on the fix? Are we sure this is a software issue?

  • Any news on the fix?

    You will see a post by a Garmin rep identifying either a beta release or a final release when an update is ready.

  • I have similar issues off and on with Fenix 6 Sapphire.  The most common problem is erratic readings - jumping from 135 to 145 or even 155-170 and then back down over the space of 5-10 seconds.  So I started wearing HRM-Tri and never see that kind of behavior, so I think it was the watch, not my heart.  But now after ~6 weeks, the HRM-Tri suddenly stopped working (battery change didn't fix the issue).  I'm wishing I never gave up my FR 235 which did a much better job of HR monitoring, and even was able to monitor while swimming laps using a 3rd party app.  Other than that, the F6 is great for all the other features.

  • Thank you. Could you please advise where to look for that post? This watch is my first Garmin product, so I'm not very familiar with how the fixes are announced and where to check for possible upgrades / fixes.

  • I had that problem on my Garmin Vivoactive 3 but my Fenix 6 Pro behaves really well. I get the heart rate readings that I expect from my workouts, trainings and resting HR. My resting HR is normally low like 45-50 which the watch captures well. My cardio is normally between 130 and 150 and the watch is in the range. I even think that the HR adjustments with 1 minute intervals is pretty good. While running outside the watch is also accurate and adjusts pretty fast. I wonder if Garmin sourced different parts for the HR sensor that could explain this huge differences in people's experience with the HR. I read somewhere that they are working on a fix.