Poor ANT Connectivity

Just went for my first short bike ride with my f5, with the following ANT devices paired:

Stages Power Meter
Garmin HRM Run
Garmin Speed Sensor
Garmin Varia Rear Radar Light
Garmin Tempe Sensor

All of which I'd previously paired and set-up with my f5 without any problems. All of these devices (apart from the Tempe) were also paired with my Edge 1000 mounted on my handlebars.

Previously, I had all of these (except the Varia) paired with my f3 and the only connection problems I'd encounter during rides would be the Tempe (mounted under my saddle) would sometimes drop out for a single 1-minute reading.

However, with my f5 it's a different (and not good) story - Even before I started the ride, my Stages PM kept disconnecting and reconnecting, and at the end of the ride there's no power recorded at all. During the ride I kept getting messages come up on the f5 that the Varia light had disconnected and reconnected several times. Connection with the Tempe seems to have been lost for about 80% of the time as the temperature shows long blocks clearly taken from the f5's internal sensor (where it's much warmer as it's picking up skin temperature). The heart rate trace also shows a point where it's dropped the connection with the chest strap.

As I said, my setup is the same as I've been using with my f3 for the last 2+ years and apart from lots of very short Tempe drops, I never experienced anything like this. I've also checked the activity as recorded on my Edge 1000, and everything's fine on there.

Is anyone else experiencing similar?

FIT file can be found here: https://www.dropbox.com/s/eei3y3sfcj8151d/73JD2214.FIT?dl=0
  • With a different set of sensors (except for the Tempe - which works OK with other devices) a similar result - this does point to the common factor being the Fenix 5 I'm afraid. The bright side of doing a master reset now, is that you only have the device for some days.. no VO2Max, LTHR lost yet (probably).


    Yeah, I thought the same so decided to get a master reset out the way last night when I had some spare time to configure everything again afterwards. Hopefully I'll get chance to see if it's improved things later on today.

    The first FR230 my wife got wouldn't connect to any ANT+ sensors at all. The replacement was fine. You may have just been unlucky.

    Do you even need to go though Garmin? Contact the place you bought it from and see if they can swap it out.


    Yes, I could just exercise my rights and exchange it (might have to wait a bit though if my supplier has no new stock yet). I have reported it to Garmin though to bring it to their attention in case other people experience similar. If it's something Garmin can't resolve quickly then I'll exchange it for another f5 and hope for the best.

    I'm really hoping this is just a problem with my f5, but I would have thought it would be an "either works or doesn't" problem if it was. On the other hand, if this was an inherent f5 issue then I'm sure someone else (including the early testers like DCR) would have picked this up by now.
  • In your activity on Garmin Connect you will see the drop out in the Heart Rate plot.



    Once you have paired it with your watch and start wearing it, it will come out of standby and connect automatically once you select an activity (the heart symbol will stop flashing and you get a connection message). After you take it off it will go back into standby on it's own.


    Thanks for the info. For what it's worth in my testing it appears it actually wakes up when you put it on. It doesn't seem to be a requirement that you start an activity. It has connected and was sending data to the heart rate widget after wearing it for a few seconds.
  • Well I just tried another indoor ride, and I couldn't keep a connection between the Stages PM and the f5 long enough to even start the ride (this was after a master reset of the f5). The f5 would take ages to connect to the Stages, even with the Stages stationary and the f5 held about 30cm away from it - and when it did finally connect, within a few seconds it was gone again. For reference, I then tried my f3 and Edge 1000, both of which formed a solid connection with the Stages right away.

    The obvious conclusion is that this is down to something with the f5, but saying that it doesn't have the same problem (at least not as bad) with other devices it's paired with (I ended up pairing it with the ANT+ power output from my Tacx Neo and that held solid). I guess that's maybe down to the f5's reception being poor, but other devices outputting a stronger signal than the Stages which means they're not dropping quite as bad.

    I actually have an f5S coming from Amazon tomorrow which I was just going to refuse delivery of (I forgot to cancel it and it's too late to stop despatch), but I might actually do a quick test with that and see if it's any better.

    It would be good to know it there was anyone else with a Stages PM and a F5 out there!
  • Gates Fore

    Well I just tried another indoor ride, and I couldn't keep a connection between the Stages PM and the f5 long enough to even start the ride (this was after a master reset of the f5). The f5 would take ages to connect to the Stages, even with the Stages stationary and the f5 held about 30cm away from it - and when it did finally connect, within a few seconds it was gone again. For reference, I then tried my f3 and Edge 1000, both of which formed a solid connection with the Stages right away.

    The obvious conclusion is that this is down to something with the f5, but saying that it doesn't have the same problem (at least not as bad) with other devices it's paired with (I ended up pairing it with the ANT+ power output from my Tacx Neo and that held solid). I guess that's maybe down to the f5's reception being poor, but other devices outputting a stronger output than the Stages which means they're not dropping quite as bad.

    I actually have an f5S coming from Amazon tomorrow which I was just going to refuse delivery of (I forgot to cancel it and it's too late to stop despatch), but I might actually do a quick test with that and see if it's any better.

    It would be good to know it there was anyone else with a Stages PM and a F5 out there!


    For what it's worth I have the F5 paired with the HRM-Run and the footpod. Looking over the data there appears to be no drop outs at all with the HRM-Run. It's harder to tell if the footpod is losing connection but the icon stays solid in the activity screen before I hit start.

    I will say that the bluetooth range of the watch is worse than other bluetooth LE devices I've paired in the past. I have to keep the phone pretty close. That may backup your findings of weak antennae.
  • Thanks for the info. For what it's worth in my testing it appears it actually wakes up when you put it on. It doesn't seem to be a requirement that you start an activity. It has connected and was sending data to the heart rate widget after wearing it for a few seconds.


    Yes, you are correct it will wake when you put it on. I just meant from an activity point of view it will connect automatically once awake.

    It does sound like you've been unlucky with the F5 you have. I think we would have seen a lot more reports of problems if there was anything systematic.

    I hope you can get it exchanges promptly and start enjoying the new one.
  • Former Member
    0 Former Member over 8 years ago
    If you google search stages PM dropouts your eyes will bug out. the stages PM puts out a far, far weaker signal than other power meters and so people for years have had issues with everything from the Fenix 3 / 920XT etc. to even Garmin Edge computers that were on "out front" mounts with the Stages. It certainly is not a great sign that the Fenix 5 is struggling when your Fenix 3 did not but it seems many/most other ANT devices, PM etc. put out very strong signals that can be detected many many feet away (sometimes a PM can be read in chase cars) so some watch developers are actually putting in smaller less sensitive antennas in their new products (cost or size savings?) since the source signals are generally so strongly powered, which works fine until you run up against something like stages which is far weaker than most others and then suddenly you have a problem. not that this is an acceptable solution but the 4iiii crank arm PM puts out a very strong signal and doesn't have this issue.
  • Former Member
    0 Former Member over 8 years ago
    Yes, you are correct it will wake when you put it on. I just meant from an activity point of view it will connect automatically once awake.

    It does sound like you've been unlucky with the F5 you have. I think we would have seen a lot more reports of problems if there was anything systematic.

    I hope you can get it exchanges promptly and start enjoying the new one.


    I think I might be suffering from a similar issue; I've noticed that when wearing my HRM Run, outside an activity, it seems to just drop out after a while. According to the watch the battery is good, so that shouldn't be a problem.

    I tried my first HIIT class, with the HRM Run, today and, well, I don't know. I'm not sure if it dropped out and the watch optical HR kicked in. The activity is below, but I'm not sure how to check..

    https://connect.garmin.com/modern/activity/1631258470
  • Can't help sorry, but that sounds like a complex setup ! Mine is rather more simple : HRM+Footpod and so far so good
  • If you google search stages PM dropouts your eyes will bug out. the stages PM puts out a far, far weaker signal than other power meters and so people for years have had issues with everything from the Fenix 3 / 920XT etc. to even Garmin Edge computers that were on "out front" mounts with the Stages. It certainly is not a great sign that the Fenix 5 is struggling when your Fenix 3 did not but it seems many/most other ANT devices, PM etc. put out very strong signals that can be detected many many feet away (sometimes a PM can be read in chase cars) so some watch developers are actually putting in smaller less sensitive antennas in their new products (cost or size savings?) since the source signals are generally so strongly powered, which works fine until you run up against something like stages which is far weaker than most others and then suddenly you have a problem. not that this is an acceptable solution but the 4iiii crank arm PM puts out a very strong signal and doesn't have this issue.


    Yeah, I know the Stages broadcast power isn't exactly stellar, though personally I've never had a problem with my f3 or Edge 1000.

    I've just re-tested it with a fenix 5S, and disappointingly the results were the same - it took me several minutes to even detect the Stages PM to do the initial pairing, and then when it did finally pair, it couldn't maintain a connection for more than a couple of seconds, even with the crank stationary and the f5S held within 20cm of the PM. Unfortunately, this would seem to rule out the possibility that my original f5 is in any way faulty.

    So, it looks like the "blame" lies with both parties - Stages for their weak signal, and (it would seem) Garmin for having implemented a poorer ANT+ antenna in the f5 than older products. If it was only the Stages that was causing issues, then I'd say this wasn't a significant issue as far as the f5 series was concerned. However, the fact that I also experienced other dropouts (Varia rear light, Tempe and chest HRM) to a lesser degree really tells me that the Garmin's ANT+ reception is inadequate.

    This still doesn't really explain why earlier testers haven't picked this up, but I guess if it hadn't been for the Stages mega-dropouts I wouldn't have even bothered posting about a couple of minor HRM dropouts and I'm not sure many people have a Tempe or a Varia RRL.

    So as it stands, it looks like I'm going to have to drop lots more money on a different PM and hope Garmin can do so something with their software to improve ANT+ connectivity with their own devices!
  • got any mates with PMs locally who you could try and see if it's "just" stages or the Fenix?? If your anywhere near Leeds your welcome to try against my P1 pedals.