This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Pulse Ox not working + Heart Rate not working when Pulse Ox is turned on


Got my 945 yesterday and set it up. Everything seemed to be working fine initially.

During the evening I went through some settings and turned on HRV Logging, Sleep/All-Day Pulse Ox, etc.

After this I noticed all heart rate data started displaying "--" with maybe one value every few minutes at best before going back to "--". Stress measurement started showing "Check watch fit" when trying to do a measurement and I was unable to get a single Pulse Ox reading during the whole evening. I went to sleep thinking it might just need some time to adjust.

I woke up with absolutely no sleep data or HR data for the night. After not getting more than a few blips of wrist heart rate data all morning regardless of restarts, different clock position on wrist, band tightness or even wrist side, I went back into the settings and tried turning off the Pulse Ox sensor. After this the heart rate reading updates reliably every few second and everything seems to work again.

I have now tried this multiple times to make sure. Turning on Pulse Ox in the Sensors menu makes all wrist heart rate measurements disappear and turning it off makes them work like normal again. No Pulse Ox readings have been captured at any point and can't be captured manually either.

Anyone have any info on this? Some known software issue, a faulty sensor, something else?

Software version 2.60 (2fa11e6). (EDIT: upgrading to 2.64 beta or downgrading to 2.50 does not help. Neither did 2.70.)

Lights on the back of the watch seem to work quite differently when Pulse Ox is on, cycling through a blink pattern if that is of any value, but I have nothing to compare to. (EDIT: took a video of it since it looks like the sensor in an endless reset loop: Local Garmin support said it does not look like what their test unit looks like)


  • Yes they also contacted me as well

    they asked for a video with pulse ox set to all day and then the OHR readings. 

    So hopefully that will convince them to sort it out!

  • They emailed me and asked me to send on some photos. Not sure what that will do but hopefully will lead to a fix

  • I had the button issue with my first unit. I got a replacement yesterday, plugged it in to Garmin Express to update maps, etc - sleep data didn’t show this morning, sleep pulse ox was on. Today, heart rate data has been intermittent. I reached out to Garmin support via online chat - they advised its a known issue and they’re working on a patch and to report back tomorrow if the problem persists.  Sounds like a software issue with 2.60. 

    At at least the button issue is fixed with the new device!  I certainly hope this doesn’t result in another exchange. Interested to hear how things develop for you all. 

  • Picked up the tri bundle yesterday from a local running store in Little Rock, having this exact issue. I contacted online support and the best they offered was to do a restore. That worked for about 4 hours, now no HR again.

    Disappointing to say the least, especially w/ a $600+ watch. I am seriously thinking of returning and sticking with my Fenix 5x...

  • Seems like the proposed fix is to turn off all aspects of Pulse Ox sensing (turning off all day and sleep pulse ox). Again - I sure hope this is just a software issue that can be fixed quickly. I know you all agree - $599 for a watch with button issues and now loosing Pulse Ox (no matter how useless the metric is for most of us) is disappointing. Garmin has been helpful so far, and I love the watch (if the nagging issues would get fixed) - otherwise, I’d ditch Garmin and give a competitor a try....

  • It is really not filling me with joy at the thought of buying a 945 right now to replace my Fenix 3HR right now, as if nothing else I wanted it for night time Pulse Ox to get some idea if my sleep apnea treatment is working as it should Disappointed

  • Just a quick update from my chat this morning with the Garmin support team - 

    Jordan:I completely agree and apologize for the issues, it is not a hardware problem so the watch itself would not need to be replaced. what it will be is a software update to fix the issue internally within the sensor

    Chris:Okay that is great news! Do you have any kind of timeline on when that fix would be released?

    Jordan: when I look at the case it doesn't have a specific timeline or ETA on when an update will be released but it has a high escalation to it since it has been reported from multiple sources so usually in cases like this updates come out quicker than others since it is a main priority to the software team.

  • Former Member
    0 Former Member over 4 years ago

    I´m in Norway with the euromaps and have the same issues w/ pulseoximeter not working and HR only works if Pulse Ox is switched off. Just got my new replacement 945 after I send my old for repair/replacing due to troubles with buttons sticking. The new came software 2.60 pre-installed.

    Agree the Beta 2.64 doesn't help, tried that.

    Very frustrating

  • Thanks!

    btw: Same problem here...

  • Former Member
    0 Former Member over 4 years ago

    Any update here? I've had zero reply from customer service.