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Garmin updates Fenix 5 design to address connectivity issues


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Four days ago I received the automatic email of Garmin's news release to the FCC (Federal Communications Commission, which has to certify all devices that emit signals in the United States).

Generally, when it is published publicly at the FCC, all the most "compromising" information is blocked to keep the product secret until a few months after its presentation has been effective. This is entirely logical, as no manufacturer is interested in revealing all the details of its product before it is released, neither to the general public nor mainly to competitors.

I was surprised to find the Fenix 5 again and, above all, with the whole file open, so it could not be a new version of the Fenix 5 that included Garmin Pay and the possibility of playing music, like the new Forerunner 645I didn't give it much thought until yesterday when I received mail again with new documentation that had been uploaded to the fileThe IPH-A3119-00 is the first of its kind in the world, and it is known internally as the IPH-A3119-00.

This new document was a letter accrediting the permissions to make permitted changes to the regulation, due to an internal redesign of the antenna and the alteration in the signal transmission power.

Permissive change letter

Garmin has made modifications to the antenna used for ANT+ and Bluetooth data transmission. These changes lead to an increase in the transmission power of Bluetooth and ANT+ on the 2.4GHz frequency. In turn, Garmin has had to reduce the transmission power of WiFi (which works in the same band) to maintain the same effective radiation power (or EIRP, equivalent isotropic radiated power). And now I will explain why.

The problem

Since the first arrival of the Garmin Fenix 5 on the market, some users have complained of problems with the use of ANT+ sensors - not so much heart rate sensors, but more related to cycling or running power meters. For example Stryd does not include the Fenix 5 among the supported devicesThe pulse sensor is always very close to the clock and nothing gets in the way of the signal, but power meters can be more critical because of the distance and because the body (composed mainly of water, which does not allow digital signals to be transmitted) could be placed in between.

I really didn't have any problem with the Fenix 5, and I used it with a lot of sensors as I always do, and far away devices, like power meter or even the Garmin Varia radar, which is the biggest problem because it is always located behind the body. In all the time of use I didn't see any kind of disconnection or warning.

I had noticed these disconnections before, but on other devices, for example with the Garmin FR735XT, which I tried two different units. The first one disconnected from the radar quite frequently, the second one never did. Similarly, the connection with the phone was much more reliable on the second model.

I simply put this problem down to something similar to what happened to me, some units "manufactured on a Friday". But it is clear that if Garmin has gone into doing a redesign there is something else behind it.


Models affected

At the moment the only model that has undergone the redesign is the Fenix 5. The Fenix 5S has another model number and so far there have been no changes.

The Fenix 5X is not affected as it maintains a very similar design to the Fenix 3 HR, which does not suffer from this problem. And the other model that could see similar problems, the Forerunner 935, is not affected either because no matter what design its antenna has, there is no metal in its construction so there is nothing that can interfere with the signal transmission.

In fact I use the FR935 very often and the connection is very solid and powerful, especially remarkable with Bluetooth as I can leave my phone upstairs and still receive notifications if I go downstairs.

The solution

As I indicated at the beginning, Garmin's solution was to modify the antenna design and vary the transmission power, at least in the case of the sapphire crystal models, which are the ones that include WiFi.

And I'm talking specifically about antenna redesign, not software modification, because that's what the letter you saw above includes. So it's not something that can be applied to previous models with a simple software update, or at least I understand that it wouldn't be applicable.

Will there be a mass call to technical service?

I doubt it very much. I think that not all watches are affected, at least in my case it wasn't because I didn't notice it at any time. I can say that the FR935 has more transmission power, but as I say it is something more related to the use of steel in the case (fiber in the FR935). In my case at no time the watch prevented me from using it normally.

Besides, not all users connect their watch with external sensors, beyond a heart rate sensor. Logistically, to call for a revision of the millions of Fenix 5 that have been sold is crazy. What I am sure is that now the warranty claims (and out of warranty) that may occur due to this circumstance will be better attended to, and I am sure that in one or two months all the technical services in the world will be ready to attend to the incident in a fast and effective way.

Should I contact technical service immediately?

No, because you won't solve anything. If you really have sensor disconnection problems, I would wait for a reasonable time because sending the watch to the technical service now won't solve any problem.

I'm going to buy the Fenix 5 now. Will it be affected?

It is impossible to know if it is a new model or a new reference, so there is no way to know if your watch will come with a redesigned antenna or not. If you are going to buy it in three months it is also impossible to know if it will be a new unit or if it comes from a store. But it is true that it is not the most comfortable situation to buy a watch that is not exactly cheap.

I hope I was able to clear up all the doubts about it. When I published the news yesterday on social networks, there was a certain amount of commotion on Facebook, and the lack of space and time to clear it up has generated quite a few doubts, so I hope you can now understand what the situation is and what has changed in the redesign.

If any telecommunication engineer has a free time this weekend and wants to take a look at the broadcast and transmission power reports, here are the initials (1 and 2) and you can compare them with the new ones (1, 2 and 3) I'm sure you can shed more light on this than I can, as my knowledge is limited.

And if you have any questions left... you know, below are the comments. Thanks for reading!

Eduardo Mateos

I've been surrounded by electronic devices of all kinds for more than 25 years. Using them, testing them, taking them apart and dissecting them. Long distance triathlete: I swim, run and cycle for a long time. Maybe too much.

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  1. If Polar doesn't release their new watch, or Suunto a video showing Spartan's connection capabilities, they would be missing the opportunity to make the Fenix 5 really a problem for Garmin

  2. Thank you for the crack information, in my case even though it is not relevant, I have changed a Garmin Edge 520 up to 4 times because the barometric sensor was or is going quite badly, until they sent me one that was working correctly. The question to Garmin would be, why yes and no? Faulty items from the component suppliers?
    A salute.

  3. Taking advantage of this post, I wanted to know if anyone knows if this also affects the GPS receiver? When I download my races I see that the course is nothing exact, it has many peaks even crosses the rivers. Is this a defect of the clock or configuration?
    Thank you

    1. Same thing happens to me... see if anyone can explain it to us. On a bike it never happens to me so I think it's a software problem rather than a hardware one

  4. Well, I have a Fenix 5 (previously a 3) when I use a bluetooth headset to listen to music from my mobile phone, the clock is constantly disconnected (with the same headset and mobile I did not have this problem in the F 3) I realized that the problem was solved by changing the watch, the bluetooth receiver of the headset is on the right side, reading your article I think this is the problem, I consulted with Garmin and they did not give me a solution Do you think I can ask to update my watch because of this problem?
    In addition I have detected that the distance indicated by the watch does not correspond to the distance shown in the G.Connect App, I have checked with other watches and the correct distance is the one shown in the app, the one shown in the watch is much lower, did you have news of this failure?
    Thank you very much.

    1. This problem has nothing to do with the design of the antenna, it is a limitation of Bluetooth by design in terms of transmission capacity which is only 352kbps. If this bandwidth is occupied by music playback, the watch obviously loses the connection because the phone is prioritizing playback.

  5. I was having problems with constant disconnections from the bluetooth to the smartphone, with something so sanctioned with crossing my arms, or putting my hands behind my back, after 10 mails to the SAT Garmin (treating me like a fool...) I demand that the warranty be executed, which they give me an RMA and I send it by SEUR, after a few days, they answer me saying that they cannot repair my Fenix 5 and that they proceed to send me a RECONDITIONED unit from the UK stores and that it will be available in 15 to 20 days, plus 24h or 48h of shipping to my home... I think they have lost a customer to me. I demanded a new unit or mine repaired and the answer was a resounding one, WE ARE IN THE FRAMEWORK OF GOOD LEGALITY. In short, if you like it well and if not, so do I. Anyway... you have already seen me at Garmin...

  6. I think garmin has products with excellent ideas and market functions. But only when they work well. There are always problems.

  7. Like almost all, keep in mind that they are very advanced products, they are not simple smartwaches, and they are releasing models with the pressure of the competition not being many times "mature" polar or suunto are not escaping either....

  8. The garmin fenix 5 is always being updated, the pulsation sensor doesn't show anything in the last 4 hours and I have already taken it to be repaired. It has been returned to me the same way from the technical service. I am very upset with this watch, it only has problems and decathlon doesn't want to take care of it even though there is a year and a half of warranty left.

  9. I received the watch 2 days ago, the fenix 5. One pass. I bought even a watch cover. And on the way come some protectors. I love the design and looks of quality, but ... continually disconnects from the mobile and when it does it costs hours to reconnect it!
    I wasted 2 days doing what the SAT told me to do and I'm sick of it! I'm sorry to say that I'm going to give it back. It's a shame that a 600 euro watch has these problems. My 15 euro xiaomi bracelet has never had these problems.

  10. I have the FR 935 and I'm having trouble with the optical heart rate sensor with blanks in the 4 hour intervals, it just turns off the sensor's lead light for seconds. Hardly any sports activity works at the moment.
    I have had two Fenix 3's and switched to this model because the altimeter sensor, barometer and temperature in the two Fenix 3's failed.
    The Sat dé Garmin didn't solve my problem and by giving me a hard time at the mall where I bought it I managed to change it for this model that also gives problems.
    I have seen users on the network who are affected by these problems and are going to make a joint complaint or denouncement.

  11. I got a grmin fenix 5 I bought two months ago and the connectivity is going great so far. But the LED on the optical sensor is constantly flashing (like a very fast blinker). When I activate the pulse display or do an activity the light stays on. The truth is that the pulse readings seem consistent but I don't know if the blinking is normal. Does anyone else have it?

  12. sorry I did not understand very well of the watch Fenix 5s if it has antenna for poderlo connect to Zwift and I tried in configuration-sensors and accessories-FC on the wrist and finally in the option Transm. in act. -On.
    but it doesn't connect to me, I hope it is possible with this watch. Can you confirm if it has Ant+

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