New 2021 GPS Accuracy Issue Impacting Some Garmin, Suunto, other GPS Devices

Update: As of Sunday morning this should be resolved, however, you’ll want to ensure your GPS has fully synced before heading out, and it doesn’t hurt to give it a few extra mins outside before pressing start.

Just a super quick post to provide a tiny bit of context on an issue some (but not all) folks are seeing where your recorded GPS track is offset by upwards of a hundred meters or more. In general, the pattern of your route is correct, but it may be displaced to one side or the other. However, in many cases by the completion of the workout, it sorts itself out. In other words, it’s mostly a one-time issue.

The issue largely appears to be impacting companies that leverage the Sony GPS chipset in their devices, which is basically all new Garmin devices in the last few years, most new Suunto devices in the last few years, all Polar devices in the last few years, all COROS devices, the Wahoo RIVAL, and more. More or less everyone except Apple.

Very rough list of impacted devices (I’m missing a ton here, these are just the most popular ones)

– COROS GPS watches (need to double-check original Pace though)
– Garmin Forerunner 45/245/745/945/Fenix 6/MARQ/Vivoactive 3/4/Venu
– Garmin Edge 130 Plus 530/830/1030 Plus
– Polar Vantage V/M/V2, Grit X, Ignite
– Suunto 5 & Suunto 9
– Wahoo RIVAL

Again, I’m missing a boatload here, but that’s the big-ticket ones off the top of my head.

All these companies have switched to the Sony GPS chipset since around 2018, with Polar and Suunto initially jumping onboard, followed quickly thereafter by Garmin, COROS, and more. The Sony GPS chipset is widely used by these companies because of the power savings delivering longer battery life.

But – that’s all besides the point, and not the cause of the issue. The issue has to do with the ephemeris data file, also called the EPO file (Extended Prediction Orbit) or Connected Predictive Ephemeris (CPE). Or simply the satellite pre-cache file. That’s the file that’s delivered to your device on a frequent basis (usually every few days). This file is what makes your watch near-instantly find GPS satellites when you go outside. It’s basically a cheat-sheet of where the satellites are for the next few days, or up to a week or so.

Your watch or bike computer automatically gets this file via Bluetooth Smart from your phone, WiFi, or USB, depending on how you connect your watch. Most companies deliver it anytime your watch syncs and needs a new version. So from your side, you never do anything – it just quietly happens in the background.

Right now, the data in this file is wrong, and thus the data your watch uses for those first few minutes is also wrong – leading to the offsets. You can see an example of this below, from one DCR reader:

image

And another:

image

As the watch sustains its connection with GPS satellites over the length of the workout, it’ll generally re-correct itself as it pulls in updated data from above. Most people are reporting that it’ll resolve itself either by the end of the workout, or the next workout. You can see that here from yet another DCR reader:

To help resolve this, you can simply stick your watch/bike computer outside and let it record an hour workout, then just discard it after that. It’ll have received the required satellite information to likely correct itself.

But it won’t impact everyone. For example, I tried today with two Sony-based watches (Garmin FR745 and FR945) to get it to lay down an incorrect track – and it wouldn’t. I suspect this is because in my case the watch had been bumped on a few times while playing with my kids yesterday and today, so my guess is it had already re-downloaded what it needed to be correct out of the gate. I also tried with two non-Sony chipsets (Fenix 5S and Apple Watch SE), and didn’t see any problems either.

In talking to Garmin today, they’re working on a fix for the issue, that they believe will most likely be that they just update the satellite pre-cache data from the server, which in turn your watch will grab just as it always does. But first they (and others) are working to sort out what exactly is wrong with the data that’s causing this.

In talking to another person in the industry dealing with the issue, they noted that technically 2020 had 53 weeks, and this is the 53rd week. As such, the suspect Sony data file issue might actually be tied to that complexity.

See…just when you thought you escaped 2020, it’s still there waiting for you at the start of your run.

With that – thanks for reading!

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211 Comments

  1. Michael

    Hi there,
    thx for this information. I had it today, that my fenix 6 recorded the track a few hundreds of meters off my real track. Hope this will be fixed soon!
    br Michael

  2. cybirr

    (Retired military, used GPS since the early 90’s)

    We had on our devices something called the “almanac” that was received via a very sloooowww transmission rate direct from the GPS satellites. This was the EPO/CPE you are referring to. We’d have to leave the unit out-and-on for an hour or so and it would receive the data (early 90’s). This was done every few months as I recall. Modern units, it was never an issue. I thought that process was part of the basic GPS standard. I’m surprised that is not incorporated into all these consumer devices.

    • Jani Ollikainen

      It is, It can get it from the GPS signals, but it still says that it’s Expired.

      I tried deleting CPE.bin, power cycled the watch, put the watch on hike, waited 6mins.. Now I got new CPE.bin file, which was still “Expired”, and it’s pretty small 2kb, compared to 935’s EPO.

      Which makes me think that it’s some bug in the Sony’s GPS firmware.

    • cybirr

      Your supposition about the Sony firmware being the culprit seems legit. I noted you mentioned the 6-minute cycle for the modern download so I’ve no doubt your refreshing the file. Interesting.

    • Alex

      @cybirr – just to make you feel better about consumer devices, they can download the almanac via GPS. They just do it through the phone so you don’t have to wait the whole 12 min to download it via GPS.

  3. Jon Thornton

    Garmin Edge users can assess GPS accuracy using the widget I wrote a couple of months ago. link to apps.garmin.com

    • cybirr

      Thanks for that link. A couple firmware updates ago Garmin removed the GPS accuracy data field. The signal strength is still there but not the accuracy. I thought it was a nice-to-have data field. Thanks for offering this app.

    • Jean François Donnay

      Accuracy is still there,
      Press the activity circle,
      then press the screen to see the house and the 2 arrows,
      then press the right arrow until the page opens from which you will have access to the satellite view

  4. bertil

    Thanks! Apart from today and yesterday, I had this problem one time before with my FR 245, on 20 September 2020. One of my Strava contacts had the same issue around that time, but I didn’t read anything about it anywhere else so may be purely coincidental.

    • L.Janssens

      Thank you so much for posting this! In the last 16 months or so using Polar Ignite, I had this issue exactly once, which puzzled me. Just checked after reading this, and it was on Sept. 20th!!! Starting at 3:38pm (Brussels time), and “was back on track” after 14min30sec (ie 3:52pm).

    • bertil

      Thank you too! That day, my 30 minutes run started 2 minutes before yours but didn’t correct itself. It was near Amsterdam so probably very bad gps reception in the entire Benelux :). My friend’s faulty run was on 16 September, however. He also has a FR245.

  5. Paul

    Suunto 9 user here – first occurrence for me was at 2am UTC on 31/12. I’ve been leaving my watch on a window sill for 15min before every run the last couple of days.

  6. David Harris

    Is there anyway to fix the gpx file after the fact?

    • Jon Palmer

      I’d love to know if there is a fix for the files too, Strava segments are borked without it.

    • Realistically, no.

      I mean yes, technically one could painstakingly re-construct it manually second by second with low level file editors. But it’d take you a long time and there’s a good chance it’s be flagged by Strava’s file checks anyway.

    • Jani Ollikainen

      There was python script in the Garmin forums:
      link to forums.garmin.com

      But realistically I don’t know how his case works, mine have been broken in different offsets, over 3 hour run on 1st, my starting and finishing points were the same, but the GPS track shows them to be in totally different offsets.

    • Bob

      I exported to GPX and imported into QGIS to see what was going on before I realised this was a wider issue.
      I found the start of my run was completely wrong, couldn’t even find an offset that matched. The middle of my run was offset to the north west. The last part of my run was offset to the north only. There were also a few bits between the different offsets that were pretty weird, i.e doing little u-turns and loops.
      So in my case it wasn’t really worth the effort to fix especially since the distance seemed about right.

      If your track just has one offset, it’s pretty easy to fix in QGIS and reimport to Garmin.

    • Jon Palmer

      That script worked for me. My run was out but the same offset for the entire activity so the script was perfect once I calculated the right offsets. Had to delete the original from Strava to avoid getting flagged as duplicate.

    • David Harris

      Ran the script and it worked for me.

    • Colin

      FYI – if anyone has an activity that they need to move (i.e. the whole thing is just offset), I was able to drag mine to the right place using the WTracks tool. Link here link to opoto.github.io – it’s a simple load up of your gpx file, drag to the right location, and save. You can also do other editing etc if needed, but it was perfect for my needs.

    • Sd

      Can you please tell me instructions on how to do that? I can’t figure it out ?

  7. Tim Grose

    Yeah I had an “offset” track for about 15 mins yesterday (1st Jan) on a 945. I stopped for a moment then to check where was heading and maybe that helped correct things and was OK again after and fine today.

  8. Keith

    Just to feaffirm what you already stated, i had no issue with my 2016 Suunto Spartan Trainer. It does not have the Sony chipset.

  9. Chris

    Not understanding how calendars work is a pretty weak excuse for a company that’s been producing GPS units for 30 years. I’ll *maybe* give Suunto, COROS a pass. But that’s why I’m supposed to feel good about paying more for a Garmin device, right? That they understand how GPS works?

    Another example of “Garmin’s Biggest Competitor Is Their Own Software Instability”.

    • Except Garmin had no control over this. This is literally the file from Sony. Just like everyone else (Wahoo/COROS/Polar/Suunto/etc…), they just pass it along.

      There are many things one can assign blame to Garmin for, I think this one is probably a stretch.

    • Chris

      Without starting a whole big thing, I’m not so sure Garmin is blameless. Why isn’t the FR 745 affected? And more to the point, they made the decision to switch to the Sony chip, so they bear some responsibility for the downstream consequences. I have been really unhappy with the Sony GPS accuracy even before Jan 01. Today I took my old FR 230 for a run and got the cleanest GPS track in years.

    • The 745 is affected, as noted, it’s not a comprehensive list. Just skipped my mind on the Garmin side, there are boatloads more there that use it (like, dozens).

    • Chris

      FYI: Not a single user report of this problem on the FR 745 Garmin Forum. And a lot of people positively stating no problems with it on the Reddit Garmin forum.

    • Piotr

      I think the Garmin should have control of the components it uses though. In the end if the GPS watch does not work well, users do not care whether the problem is with the Garmin or the Sony chipset. They bought a Garmin smartwatch and Garmin should ensure that the components it uses works well

  10. Dan F

    Hi there, this definitely affected my COROS Pace v1 this morning and to a lesser extent yesterday. No satellite updates in the app so it’s likely the bug you noted. Here’s hoping tomorrow’s run is better. Did result in some Strava CR I definitely didn’t earn though! 🙂

  11. Steve W

    Had that issue yesterday (50 minute run) and today (25 minute walk) with my FR945.

  12. John B

    Finally a post that validates my not upgrading my Edge 520.

  13. pavlinux

    Fenix ​​5 Plus use MTK3333 chipset!!!

  14. Don

    FR245 user. I ran about an hour each the 1st and 2nd and the offset never corrected – the start and finish lined up, just a couple blocks SW of my house on the map. New routes in both cases so I can’t verify the distance without running them again but it seems like it’s probably correct.

  15. Jean François Donnay

    So EPO (=CPE) is also expired in my Edge 1030 plus

  16. pavlinux

    > Right now, the data in this file is wrong,

    There is no data at all, the file is only 2048 bytes!
    link to pastebin.com

    • NiceTryHacker

      I’m not clicking this link, gotta keep my computer clean. (like my race singlet for 2020 … not used once 🙁 )

    • There’s nothing wrong with what Pavlinux posted. It’s literally just a screenshot showing the empty EPO file data, and the link is simply the actual text (contents) of the file (since pasting it here would look fugly).

      It’s good to be careful about clicking on links online, but this isn’t that.

  17. Rich

    Thanks Ray – seemed weird my FR945 was off track by a few hundred metres for the first couple of kms on yesterday’s run. Now I know why!

  18. Wyatt

    It only took 21 years for Y2K to hit, and in the form of affecting GPS devices… ?

    • ChrisTexan

      LOL, Y2038 bug is still coming, right around the corner (okay, well, one generation around the corner, hopefully everything depending on 32-bit time will be long removed by then.

    • h m

      Gps weeks use 10 bit encoding so there is a rollover every 1024 weeks. We have had two 1980….. the most recent was in 2018 iirc

  19. Anon

    Any insight into if the bad recordings will be corrected as part of the fix or if it will be possible to do so manually?

  20. Erez

    Maybe I am missing something. The CPE file hints the watch how to acquire the GPS signal but once acquired the data is correct. If I am starting my activity after acquiring signal why do I still see the offset?

    • Reid

      The ephemeris (location) data from the satellite will eventually correct itself, as Ray mentions. Until then, the incorrect position of the satellite will impact the determined ground position of the receiver.

      At a basic level, the receiver receives the GPS signal and compares that time stamp to when the signal was sent. Using the ‘known’ location of the satellite, a circle can be drawn on a map showing the required distance from the satellite to the receiver to result in whatever time lag there was for the receipt of the signal. Doing this procedure across a minimum (ish) of 3 satellites well get you your lat and long (the circles will only intersect at one point (ish)), 4 will get you altitude ( 4 spheres, etc…).

      Anyway, it all comes down to GIGO – garbage in, garbage out.

    • ChrisTexan

      To try and clarify Reid’s response a bit further, if I tell you (via CPE) that “Satellite A” is at position A, and Satellites B and C are at positions B/C, and you receive a time signal from each of them with “x/y/z” offsets, you say “okay’ I’m at position 1. If you have nothing else correcting you, but those satellites are actually at positions D/E/F, that first point is now offset incorrectly, and you are in the wrong place, GPS-wise.
      Eventually, the correction signals that the GPS satellites/system itself sends out, will tell you “no, the locations are D/E/F”… BUT by the time you receive those corrections, you may have lost signal to Sat-B, and picked up Sat-G… and your (still wrong) hint file says “Sat-G is over here at pos G”… so you correct A and C, and correlate with bad data for G, and have new offset 4… but that position is still wrong (likely much less so as you have 2 out of 3 “right”)… since a typical GPS receiver bounces between 5-7 or more satellites based on signal strength and loss, it may take awhile for it to sort out where all the “REAL” offsets are on those satellites, which is why you start seeing the course corrections “mid-run” and sometimes 2 or 3 or more corrections getting closer and closer to “on-track”.
      Eventually, your device will resolve all visible satellites “correctly” and all is well again, but that takes some time. And if, after that, the device “syncs” back to something that replaces the in-memory updates, with the still-invalid “CPE” file, it may have to start all over again on the next activity.
      Thus the recommendation to start your watch on an activity “start screen” well in advance until you have a new valid CPE file, ideally in open sky, to give it a chance to “self-correct” at least most of the satellites that are in good signal range, thus resulting in a good starting point and less chance of dependency on the CPE data for “new pickups” along the way.

    • Erez

      Thanks Reid and Chris for the articulated explanations.

  21. Stephen Gunn

    Does it make any difference if you use GLONASS or Galileo I wonder?

    • Riaan

      No, not at all. I had this very issue described in the article on the 1st 2 and and again today. Today I experimented with GPS only, GPS and Galileo, Gps and Glonass. No difference. All had the offset – except when the next activity was in only a few minutes from the 1st.

  22. Felicia

    Seeing this issue too with my Venu! The first .25 mile or so of my walks from 1/1/21 and 1/2/21 are starting off in the desert wash near my house, instead of my actual start. It eventually corrects itself and works as expected for the rest of the activity. And I thought it was just me having a problem! Thanks again, Ray, for providing us with valuable and timely information 🙂

  23. Ray Venables

    Interesting explanation! My question is this: why is my GPS data offset in Zwift’s Watopia? I mean, it’s a virtual world, so why doesn’t my route match up with the fictional island?

  24. S1

    Two runs today and yesterday, start point out by at least 100 metres. Is this meant to self correct?

  25. PAUL ROSAMOND

    Thanks for the info Day ?

  26. Steven

    Handily I’ve been running with both my 245 and Coros Pace 2 and whilst my 245 is clearly affected my pace 2 actually seemed fine with it’s GPS track. So maybe an older version of the Sony GPS chipset?

    I also used my 645 today as well for the LTHR test and that wasn’t affected as expected but it just reminded me how bad it was at times though.

  27. Steve

    Being 64, I actually appreciated the error as I recorded my fastest mile in years (07:15). So the gps issue was also affecting speed. For tomorrow’s run, I’ll change my foot pod and see what happens!

  28. Virginia

    Glad to know what was going on! 1st run of the year has a pretty funky GPS track, but the walk back was fine. Glad to see today’s run line up as expected (Fenix 6).

    • Virginia

      Ha got impatient today when it was slow to pickup satellites. Eventually it found me…hopefully it will get back to being able to pickup satellites within a minute or two soon.

  29. PaulaPP

    Why do you say this is a “1 time issue”?
    It only happens once, and then never again?

  30. Brian

    Thank you for this! I’ve been wondering what the heck was going on. I have a Forerunner 945, and my entire workout yesterday (6 miles) was offset. Today I ran 13 miles, and it fixed itself at about mile 3. Hopefully that’s the end of it.

  31. Doug

    945 golf user here…GPS has been off ~12 yards for 3-4 months… finally compensated by using back of green yardage for mid-green yardage. Running data seems fine. Any idea when the solution will be done? Thanks!

  32. TheStansMonster

    Holy crap – this literally happened to me just a few hours ago on a hike with my brand new Fenix 6. I was worried it was a sign of lemon device, but hoped it was just because the trailhead is up a shallow canyon. I even switched from GLONASS to Galileo in the middle.

  33. Is there a fix for Strava segment attempts? I ran hard, and it didn’t count.

  34. Colin Ingram

    Garmin car sat nav have the same issue, updated a week ago, very inaccurate now, can’t follow a road, has me going off-road.

  35. Tyson

    Can confirm I had this exact issue with my Venu today.

  36. winfij

    During a Garmin Connect sync with my F6Pro a short while ago I noticed it said it was doing a “software download” (or similar wording) and checking some time afterwards the CPE file was shown as current, whereas earlier it was showing as Expired.
    The watch and GPS fw are still showing the same versions as the last release (13.10 + 4.80) so I’m not sure quite what the update contained.
    Did anyone else get an update – are you still seeing the CPE as Expired?

  37. James

    Garmin recently posted on their FAQ that the issue was resolved and watched could be synced with Express, Wi-Fi, or could do a sync process on the phone to resolve.

  38. AdamS

    Thanks for the update. I don’t think your recommended fix will work though. I’ve a Garmin 245music and it had this offset issue on 2 runs so far. One on Jan 1 (AEST) and the other on Jan 3.

    • AdamS

      Actually, sorry, I just re-checked the 2nd run and it looks like the last few minutes of it may have been accurate so the problem might now be resolved.

      They were both short runs – 40mins and 25mins respectively so may have needed that long to update.

  39. Whitney

    I’ve had this happen today and yesterday on my Garmin Vivoactive 4.

  40. giorgitd

    Rode inside today, so no GPS. But I did a 45 min walk with the pup yesterday (1 Jan 21) with an Amazfit Bip S. Track was perfect. Anyone know what chipset is in that device?

    • giorgitd

      Responding to my own post… Google suggests that the Bip S has a 28 nm Sony GPS chipset with Glonass. Interesting…

  41. Lu Nickell

    Interesting. My Garmin sometimes tracks my runs correctly but about half the time, it will show the first half of my run only which then looks like a ran one way and never went home. Sounds like a different problem.

  42. Kris

    Guess, I’m glad I never got rid of my Fenix 3.. This sounds really irritating

  43. Val

    I had that happen today for the first time. Frustrating. The picture of my run hasn’t fixed itself yet. I’ll try putting my watch outside.

  44. Tommy

    My Vivoactive 4 had the same problem yesterday. My wife’s Galaxy watch was accurate. I think that Garmin is responsible for the issue. They even don’t notify customers about it. My next watch probably won’t be Garmin!

  45. Pat Farrell

    I’ve seen other GPS problems with two CAT S42 smartphones. The GPS signals are correct and recorded sometimes, but regularly when I am out in the boondocks, the GPS does not seem to capture any signals. I tried a second unit, and it had the same problem. I don’t know what GPS chipset they use, but its clearly a common issue.

  46. 245 garmin

    After using my forerunner 220 for 5 years and having no problems was super excited to receive the 245 for Christmas. My first couple of runs was great, but since we hit 2021 it’s totally off the mark when I check my run in the Garmin app. I ran 10k and it has me running through houses. I went for a beach walk this morning 8k and it shows I’m walking in the sea. Really disappointed and hoping this will be fixed asap

  47. Kaz

    I do not think it is only watches or CPE.

    My Skydio 2 drone had suspiciously low GPS coverage last week – during a 25 min flight above treetops I only had “2 bars” GPS coverage. That has never happened before. I have never had less than 4 bars in “open air” before. (UK South)

    It might be combination of CPE + Cloud Cover + Very low temperatures. Very Low temperature + Cloud cover = ice in clouds that can deflect GPS signals like glass buildings do. Then you might get offsets – just like when passing glass buildings.

  48. Joe

    Hi. My file shows that it is not a constant offset, but makeing lovely patterns. The Trak I ran is up right (NE)

    • Paul

      CPE has updated on my FR245 over night. It now states current so hopefully todays run will be more realistic than the previous 2 that had me making like superman and going over buildings and water

    • h m

      The error depends on which satellites are in use. When the subset used changes the error willl change

  49. Simon Kellett

    I work in the software /space industry – my first guess would be that it’s caused by new software that doesn’t allow for last year being a leap year – in space we usually use Day-of-year for recording the date, so 2020 was the first time this hit 366 for 4 years.

  50. Fabio

    unfortunatelly i think only one of my two issues were caused by this ‘bug’:

    i started at a very slow pace and my fenix6 said: 4’28/km !!! absolutly not my warmup pace…i stoped , deleted that first km and restarted. ok now i know it could be due to this ‘bug’.

    in the midlle of my run (after about 20′) my gps decided to have the following one behaviour:

    I’m not so happy with my fenix6 compared to my old 920…

    • maxfrance

      Mine just did the exact opposite, giving me a 9’+/km. my first km. (not that slow at all ..), and marking a completely out of the world track on the map as a result.

      I wasn’t aware of this bug, so I’m pretty relieved to learn about the cause; today I did a walk and soon after a run workout to check if this was fixed.

      Anyway, my Fenix took several minutes to fix the GPS signal where usually it gets full coverage in just seconds.

  51. Sony have fixed the issue and everything is back to normal again.

    Sorry guys/gals, you lost the only reason for not working out today. Because “winter” is not a reason good enough!

    • Jani Ollikainen

      I would argue/guess that Sony hasn’t fixed anything but the week number changed to 1/2021 on week starting from Sundays and that fixed the problem itself.

      My guess is improper handling of week 53’s in start of the year, where the week number is 53, but the year is changed to next one (2021) and the week numbers year is still the previous year (2020).

      But why they need to calculate the week numbers and fail this is beyond me, GPS should not need week numbers.

    • MJ

      Could this be an issue caused by the different calendar week numbering in the US and Europe?
      The US calendar week is 01/2021 while Europe uses week 53/2020, as there is one week offset in 2021 (US has Jan 1st in week one, Europe counts from the first week with at least four days).
      Wouldn’t be the first time that use of different standards causes problems…

    • Jani Ollikainen

      I thought the US week was 53 on Friday and Saturday, when the errors occured and today changed to 1 which fixed it.

      But yes, I think it’s something they do with the CPE and calculating weeks that was the error. GPS has just rolling week number but some calendar error there has to be this to solve itself in two days.

      Unix’s date has 3 different week numbers, here’s how they changed in these days:

      $ date –date=”@1609647687″ +”%c – %U vs. %W vs. %V/%G”
      Sun 03 Jan 2021 06:21:27 EET – 01 vs. 00 vs. 53/2020
      $ date –date=”@1609607687″ +”%c – %U vs. %W vs. %V/%G”
      Sat 02 Jan 2021 19:14:47 EET – 00 vs. 00 vs. 53/2020
      $ date –date=”@1609507687″ +”%c – %U vs. %W vs. %V/%G”
      Fri 01 Jan 2021 15:28:07 EET – 00 vs. 00 vs. 53/2020
      $ date –date=”@1609407687″ +”%c – %U vs. %W vs. %V/%G”
      Thu 31 Dec 2020 11:41:27 EET – 52 vs. 52 vs. 53/2020

      On which we notice that: %U and %W was 00 on those two days. Here’s what those percentage’s are:
      %G year of ISO week number (see %V); normally useful only with %V
      %U week number of year, with Sunday as first day of week (00..53)
      %V ISO week number, with Monday as first day of week (01..53)
      %W week number of year, with Monday as first day of week (00..53)

      And none of those correspond then the US week numbers if they are 1st of January is week one. And apparently there are multiple ways people use weeks in US, depending on broadcast, accounting, etc, why would you use standard weeks if you can always made up your own.

      link to en.wikipedia.org

      But yes, I think that in those two first days of the year it miscalculated the week/date/time based on it and it caused problems and there is no fix yet, it just started working again.

  52. Steve

    I don’t know whether it’s interesting or not, but I didn’t have the problem with my Garmin devices (945 and 820) but my wife did using her iPhone XS with Apple Car Play when she drove to her friends house, kept showing her off the road!

  53. Roger

    I am getting location issues with my Fenix 6 Pro S. At the start of an outdoor activity, the position is recorded a couple of hundred metres to the West of the actual and then the track aligns, but not super accurate after about 10 minutes. This has happened consistently for the past few days. However, for the past few weeks, since the latest firmware and sensor upgrade, the battery has drained incredibly fast (around 25% per hour) only during activities, both outside, with GPS and inside, without. I have carried out the all the recommended fixes, including deleting the XML file, soft, hard and factory resets, trying with and without Wifi and BT. All to no effect.

    It appears that there is a fault in the latest update, maybe leading to a very high load on the CPU (just guessing here) which impacts on the ability of the watch to calculate the initial fix and maintain an accurate track?

  54. Dominik

    It’s not a one time problem. After a 21k yesterday, a hike today, syncs with GE and GC as well as a long enough soake at the window – still being shifted about 200 meters from my actual position. CPE still not updated too.

  55. Hey there,
    thanks for the quick post. I used the Wahoo on the 2th of January and after a restart the watch worked perfekt for the first time. ? Instead I was running with the Rival (with GPS) at the 29th of December and received no Map overview afterwards. ?‍♂️
    However happy new year. ?

  56. Philipp

    Went for a run this morning. Neither pace, distance or even the route where close to accurate. The recorded route was a few kilometers west from me through the woods. And doesn’t even match the loop I’ve run. (link to strava.com) At one point I was flat out and the lap alert was telling me 5:20m/k pace, when in fact I must’ve been sub-4.. So frustrating.

  57. Gennaro

    When you deal with EPO sooner or later problems are bound to show up ?

  58. Dmitry Pupkov

    We had similar issue in July. Here is my screenshot; start and stop have been at the same point. Also, watch decided I’ve started my run at 3’000m altitude /facepalm.

    And report from another user on the forum from the same specific day/time – link to forums.garmin.com

  59. George Fertakis

    I ran on New Years day using my Garmin Fenix 6 with a friend using a Fenix 5. On the first three miles -although we were running together- the Fenix 6 was indicating a pace per kilometer 10″ slower. Could this be due to the bug mentioned here?

  60. pavlinux

    In the morning at 4:55 GMT it was corrected.

  61. Sean Kavanagh

    I was a bit worried having just fit a Fenix 6 Pro for Christmas and found the GPS worse than any other Garmin I’ve had

  62. Marco Pereira

    Great as always. Thank you very much

  63. I think the VA3 was way before the Sony era (that started in 2019 with FR*45 and Marq). I could be wrong. (Instinct Solar also put everything to west a bit yesterday.)

  64. Richard Cook

    Happened to my dismay this morning as Strava didn’t as the activity to my club leaderboard for the week ??

  65. Steve

    Something more weird is going on. My circa 2016 Garmin Fenix 3 has never missed a beat. On jan 2,2021 it took 20 minutes to get a GPS fix during a run. Usually only a few seconds. I am NOT seeing an offset though. Then when I started reading about problems with newer units I checked my system-about and my EPO is expired. Used watch on 2 activities today jan 3rd and both times still taking 10+ minutes to get a fix. I’m sure My watch doesn’t have a new Sony chipset! So why is my EPO expired and why hasn’t it been corrected even though I just synched my latest activity with Garmin connect- EPO still expired??? Is this problem more widespread?

  66. Neill Hadlow

    Thanks for this article! My Fenix 6 was working great up until 31st December and since then all the GPS tracks have been terrible.

  67. Nacho

    It definitively affected my FR945 🙁

    • Zuz

      Check this, I was running opposite direction, than made three circles.
      I have no idea what pace it was. I got new PB after this ? 1km 2:38 min/km ?

  68. Angela Tipping

    Hi there. Had exactly this on New Years Day where the track loat me for the first 15 mins and couldn’t work out what I’d done. Having just invested in a Garmin 6s I was a bit disappointed to say the least but this does explain the issue. I’ve just run a blank run to see if it can update now and fingers crossed for my run later. Excellent update! Thank you.

  69. Jay

    Got a new Garmin 830 for Christmas. Couple of rides in and no issues. Replaced my 810.

  70. Alex K

    So 15 minutes into my run on Saturday, I looked at my Garmin 745 and the distance showed as ZERO. All other parameters like time and heart rate etc were fine. When I started the run I heard the “GPS connected” beep. Had to turn my watch off, then on again.

  71. Matt Dawber

    I really should have checked here before fixing this issue on my Forerunner 945 last night ? As my wife had no problem with her run, also on a 945, at the same time as mine I assumed this was specific to my watch. A couple of observations: My run was over an hour and the problem did not resolve. Synching over garmin express and updating all the maps didn’t fix it either. However a factory reset did fix it. It sounds like just waking up this morning may also have fixed it, but in case anyone still has a problem, that’s how I resolved it.

    Thanks as always for the helpful advice Ray! Next time I will think to look here first ?

  72. Travis Melville

    If it was a UK only issue, I’d say it’s because we’ve now left Europe…. 🙁

  73. With my 245M it’s not that simple- I had an activity (Jan 2nd 2021) with a 40min “pause” (at a calisthenics parc). First part of track was shifted and deformed, second was ok. So far, so good. But 3 hours later I made a run on nearly the same track, and the new track was offset about 200m. So the device must have forgotten its position or satellite data (or there were other satellites around).

  74. I just checked my Vivoactive 4 at 07:30 GMT-6, and the CPE info is “current” once again. I guess maybe we are into the 1st real week of 2021?

  75. Jason

    Wondered what went wrong with the first 2km of my run this morning. Thanks for the update Ray!

  76. Knöll Ingo

    Run with my wife today sunday 3. and i still have the issue and had it already the last run on my 945.
    My wife’s 745 runs just fine!

  77. Rui Pereira

    Had the problem yesterday (Fenix 6). Checked this morning and CPE was updated, today’s run went without problems.

  78. Andrew Cornish

    Strava has doubled my data from my Garmin 245 Forerunner – I ran 17.45k in 1:30:00 as a Sunday Slow Run but according to Strava my route was completely different and my average pace was 2.32/k!!! I wish that were true 🙂

  79. Rob

    I did a quick run an hour ago and still I have the same problems with my FR245. I have the GOS problem since December 15. I emailed Garmin that day about the problem.

    Today I made a 6km run with 2000 meters climbing (and that is hard to do in the Netherlands). I scored some badges today that I didn’t think I could ever score!

  80. Caroline LG

    Thanks for this. I’m in France. My vivoactive 4s invented a whole new course for me today, up to 5km from where I actually was (I always do the same route…). It also said I had gone up more than 5000m! Then I tested it again this afternoon going to buy some stuff – my circular route was down as a literal straight line from my house to somewhere miles away. I hope this is fixed soon…

  81. Peter Fitzpatrick

    Well I wish I read this before my run today! It would have saved me deleting and declining my new records. Although then I wouldn’t have smashed my 1k, 1 mile, 5k and 10k records. Fenix 6 pro recorded a 54 sec 1 km and 18 mins for 10km. If only!

  82. Jackhammer

    Will this issue affect the Garmin Tatix Charlie. I haven’t seen that model of Garmin mentioned and I have one being delivered tomorrow. Not looking forward to having issues right out the gate.

  83. HJ

    I was surpised to see that I made dramatic PB this morning, until I noticed that my GPS track was way off the route.

  84. SoCorsu

    Fix !!!

    For me tested with long GPS fixing

    Affecting Garmin, Polar & Suunto Watches (Sony GPS)

    link to mightygadget.co.uk

    [Update 3rd of January 2021] Fix rolled out for Garmin
    It now looks like Garmin have pushed the CPE file update to their users, if you have phone syncing on, this should update automatically. You can also manually update via Garmin Connect
    If you check System > About and CPE and it shows expired, the update has not occurred. If you can’t get the update for whatever reason, you can still leave the watch for 5 minutes or so tracking an activity to try and let it update it self.
    The update will have been provided by Sony, so other brands affected by this problem will likely be updating currently, or soon.

    [Update] Official Garmin response
    Please be aware that we are aware of the serious GPS issue that 2021 has brought upon the Fenix 6 series watches and we are investigating reports. The issue seems to be impacting not only Garmin but some of our competitors too.
    On your watch, if you go to System > About and CPE shows Expired, please give 5 full minutes outdoors with no movement to see if your CPE file will update for you to CURRENT.
    Even if this doesn’t fix the CPE you should allow the watch to GPS soak to receive a full satellite fix. This means to wait for an additional 2-5 minutes after the device reads GPS ready.

  85. Emma

    I was running in the sea this morning???

  86. Seth Kay

    You don’t mention Fitbit. Is there a Sony chip set that has the same problem?

  87. Dave Bennett

    Had a bad track Friday (off by, 200-330m) then a good track this morning. and then another bad track tonight (Started right, ended up about 5k off) . Fenix 6 base.

    My wife had a bad track Friday (started wrong went right) and today about 15k off, didn’t even show the same track offset, just weird. 245

    Not as simple as update from phone plus it all right.
    CPE showing correct today.

  88. Matt T LeGrand

    Ok, I’ve been experiencing issues with my EPO here at the end of 2020 as well. And it doesn’t help that the out of competition drug testing has started back up again. Why can’t they just let guys like me, Charles Q. Heater, cheat at Zwift like the good lord intended.

  89. Dragan

    Just returned from the test walk with my Vivoactive 4 which was “fixed” today (CPE: Exprired turned to Current). At first it didn’t want to fix GPS so I rebooted the watch. After reboot it caught GPS signal very fast. However when I started my walk activity it started increasing the distance and showing the pace as I am running 4:40 – 5:20 which didn’t change for a whole kilometer so I discarded the activity and started a new one but it was the same.

    Anyone experiencing similar issue?

  90. George Soto

    I had an issue with my new Garmin 945, not only was the map/loc way off, but my paces were off too. Is anyone else experiencing this as well?

  91. mtn.run

    Yup, my partner and I both have Suunto 9s and had some small but noticeable discrepancies in distance. What is odd is mine did it the other day and hers just did it today.

  92. Eric

    I tried the one hour fix with my Garmin 945, didn’t work. Had two runs that put me miles away. I deleted settings and data, restarted, and after a long reboot and sync all is back to normal.

  93. Tasha

    I’m glad I found this but has anyone else has more severe variances?? The run I just finished is showing as 50km away and not even close to the same track/run pattern! Used my Garmin forerunner 945

  94. Patrick

    The problem is still there. The activities have points that are sometimes several miles away from the actual location.

  95. Craig

    I knew DCR would be all over this. Thanks!

  96. Steve

    UPDATE: EPO is now current after synching with Garmin Connect when I woke up Jan 4th 2021 Australia Time (didn’t do any activity). Fenix 3 has an MTK GPS chipset, so the EPO expired error definitely not related only to Sony chipsets.

  97. Robert1955

    Thanks for sharing. Now I understand why my Polar M on both Jan 2 and 3 started with my house under water. Let’s see what happens tomorrow

  98. Tim Chalmers

    In Sydney Australia this morning with Garmin Fenix 6 Sapphire. Mine said it was updated. Just did a 15km trail run and the GPS was at least 10km away showing me running in a built up area. Glad I use a Stryd Footpod so at least the distance and pace is correct.

  99. PaulyG

    Ran a 10K race this AM and the data on my 945 was spot on. Before the race, I did a synch (hardwire to PC) and a full power off/power on reset.

  100. Rodimusbill

    Just got. garmin Vivoactive 3 watch and so far 5 out the last 6 days were accurate. The 6th day the gps failed to get a signal at all and didn’t record anything. Now this is a brand new wT h so I’m sure it’s got all the latest updates

  101. Nick B

    Thanks for this! My Garmin 245 recorded way off the usual track on January 1 and 2; was dead on before that.

  102. Caleb

    It happened to me to!!! I have the Garmin Forerunner 45s

  103. Caleb

    This is the run that at the start of my run and in the middle of the my run is wrong. It happened January 1 and 2.

  104. usr

    Of all the possible ways 2021 could be starting with lots of sports enthusiasts getting all excited about EPO, this is probably the best.

  105. Phill Wright

    Currently living in Asia (Vietnam) and I had the same issue on a run last night, it got my distance out by over 1km (under reported) and then again this morning. This morning had me achieving a 1 mile PB at 3.52….I’m definitely not that quick.

    Thought it was my watch at first until I searched google and came across the news.

  106. Stodaro

    As of today the issue continues on my Garmin instinct solar. Each day the distance of variation is getting farther of and pace times are becoming more wildly in accurate. Prior to today the routes had the correct basic shape just shifted one direction or the other. Today the route was off by miles and the paces recorded were not even possible.

    • Scott

      I ran on new year’s day with a Garmin Fenix 6 Pro, Garmin Venu, Coros Pace, Timex Ironman R300, Timex Metropolitan S, and Amazfit GTR2 mini, all of which use the Sony GPS Chipset. Only the Garmin watches were affected by the CPE issue and had the offset issue, but Garmin uses a customized version of the Sony firmware, where the rest use standard releases of it.

      In my case the Fenix and Venu had an offset of over 300m to the West of actual position for the first hour of my 14 mile run. After that both had decoded enough of the local almanac data from the satellites in view to converge on the correct position. On the 2nd, I tried Garmin’s recommendation of waiting 5 minutes after obtaining a fix before starting a workout, but it did not help completely as the first 30 minutes were still offset. On the evening of the 2nd, both the Fenix and Venu were suddenly showing “current” instead of “expired” CPE and on the 3rd both finally worked correctly.

      The key at this point is to make sure you sync your Garmins with your phone or PC and then check the settings, about, to verify that CPE shows as “current”.

  107. RAFAEL ESTEVEZ

    The issue happended to me this morning using a Fenix 6. No matter if I change to Glonass, Galileo nor anything. The route was almost 3Km over the sea.

    Im updating now with Garmin Connect to see if it gets solved as recommended. Thanks

  108. Uwe

    So it is a 52 weeks vs 53 weeks issue? This happens all 5 to 6 years and should thus be a common issue depending on how long the code existed.

    The code base might remember the Y2K bug that was “fixed” back in 1999 by remapping 1900-1920 to 2000-2020. Now it’s 1921 instead of 2021….

  109. LFRphilly

    A couple of motorbikes in the Dakar rally got lost during first stage yesterday complaining their GPS wasn’t functioning properly.

  110. Cbarlie

    My first mile had me starting in a clump of trees, walking across a pond, climbing over a house, running through backyards and back over another house.

  111. Dan

    Glad I came across this article. I had this issue with my first activity with my new venu and had that sinking feeling in my stomach that I had wasted my money. Have been out for another ride and all good!

  112. Werner Poetzi

    I figured out that there is no offset on FR945 if you use GPS only.
    Using Galileo or GLONASS did not improve after activities, the new track always began with an offset.

  113. Theresa

    Thanks for the article. It explains the 20mile “jump” in my garmin fenix track yesterday.

  114. Anthony

    Vivoactivwe 4, Jan 1 had this issue (1 hr run) did not self correct. Jan 4 1 and a quarter hour run starts about 2km out, sort of follows an appropriate path until the turn around point (6.5kms) at which point it relocates 20km away. Does not correct at any point. I don’t believe the “should sort itself out by the end of the run.

  115. Rui Pereira

    My Fenix 6 had the problem on 2 Jan but yesterday worked ok during my long run (confirmed it was CPE updated before the run).

  116. Frank

    I had the issue on 2nd and 4th of January. Although it was faster correct again today (ride on 2nd of Jan was 3 hours+)

  117. Tim Bruner

    Rey – Since this post is related to the general topic of GPS accuracy, I’d like to submit a proposal for a future article. I’d like to get an update on where the consumer/sports gps industry stands related to the new sub-meter accuracy that is supposedly someday coming via some of the new civilian gps signals detailed here: link to gps.gov

    What does the future look like, and what kind of time frame is realistic? Are we potentially a couple years away from incredible accuracy, or is it a decade and only somewhat better?

    Hoping you can fit this topic in when there is a lull in product reviews.

    • Tim Bruner

      Sorry Ray, not sure what the heck happened there with my spelling…

    • Yeah, it’s something to chat about down the road. The main limiter there is really power consumption of the dual-band systems – which in a wearable is what matters. It’s not horrific, but it does erase most of the battery gains lately. We’ll definitely get there, but not quite.

  118. Karim

    Wow way off….

    Garmin MK2i recoding a ride on CitiBike up to Harlem to coach kids hockey. The trip home to east village was Spot on but trip uptown is screwy. Interestingly i had paused the ride during practice and i gps sorted itself out.

    Start Was way off and end was point was correct.

  119. If you truly tested these devices you’d know this has happened before with Garmin. I’ve had a run where it NEVER re-corrected itself (back in August). That Sony chipset is definitely worse than previous models (didn’t you once say it was better). Not to mention, Garmin does nothing to correct when these things go nuts. I’ve had a max pace of 60 mph during a run.

    • If you truly read what I’ve written over the years, you’d know I’m one of the most vocal critics of the Sony GPS chipset since the very beginning – well before Garmin started using it, and since then as well. It has gotten better however, and anyone saying it hasn’t simply isn’t looking at reality.

      As for this happening in August, no, it didn’t. Simple as that. You may have had a bad run, but this specific issue (and yes, details matter here) most definitely didn’t happen in August.

    • Tom

      If you truly owned a Walkman (preferably “Sport” model), you’d know Sony is simply the BEST!

  120. Simone Pillon

    Made a MTB ride this morning with my Edge 830: all is fine with my GPS track. Maybe they have fixed the problem.

  121. Rickard Hansson

    Yeah, happened me a few days ago with my Garmin Fenix 6. First kilomster war severely offset to the left but GPS was then corrected and the rest of the trail run was spot on. Looks weird, but happened only once for me.

  122. Mike

    Garmin FR45 here, running in NL. Got wrong GPS on Jan 1 run, today again. So the issue is not fixed after 1 activity. I use Galileo, will try Glonass, may that fixes it.

    • What does your CPE status show? Settings > System > About > CPE

    • Mike

      Thx for your quick reply. CPE shows “current”. I need to add that after my run this afternoon, I have tracked an activity with the watch for 90 minutes while the watch was just lying outside in my garden. This was a tip from a friend, I will check if it works tomorrow.

    • Mike

      OK, problem is solved by putting it stationary in the garden for 90 minutes. Did that last night. Checked it today and tracks OK now. Thx for the article, Ray!

  123. Adam Smith

    This is still happening.

    Did it last week. And did it this morning too. My run has been flagged for running too fast.

    How comes its bot been fixed yet!

    • Adam Smith

      Also my CPE is current. Not sire why you asked the last bloke that.

    • That’s odd.

      As for the reason asking CPE is showing current or not, because that’s a key symptom of the issue (if not showing current).

      Have you tried placing the unit outside and just letting it record a blank run for an hour?

  124. R Coetzer

    I’m using the Forerunner 245. Looks like Garmin pushed an update to my device. Since 4 Jan (in South Africa) this issue is resolved. Ran on 4, 5 and 6 Jan. Tried Galileo and Glonass, but I’m back to using “GPS only” and when I zoom in to my route it shows near perfect to the actual route I ran. Thanks Garmin!

  125. Jennifer Lynn

    IThanks for sharing an explanation! I started and stopped at the same location. As you can see from the screenshot, the map was WAY off. I’m glad to hear this issue is being resolved.

  126. AdridB

    Thanks for the info, I also noticed this hick up. It looks that things work ok with me again at my Fenix 6 Pro.

    See attached screen print.

  127. Stuart

    Just another reason to stay inside on a trainer or treadmill!

  128. Christo

    Garmin vivoactive 4 gps accuracy issues

  129. LarsHaagen

    Garmin Venu, Firmware 5.10, GPS: current, GPS FW: 4.80.

    This is still an issue!

    To begin with (January 2nd to 6th) I could wait 10 seconds to get a GPS-fix, and then the route was ok, if I didn’t wait I would get an offset.

    I had a run on January 7 for 75 minutes which was a little bit off, not much and not as bad as a few days ago, but it could not get a GPS fix to begin with, so I had to start and to the run.
    Today January 8 I went for a walk and after 15 minutes of no GPS fix I gave up.
    After 5 minutes it started a workout automatically and the route was complete off again.
    No news on the Gamin Forums.

  130. Michael

    Apple Watch 6 with 7.2 is having gps issues. I’m not alone there is a small group of us. My wife’s AW 6 7.2 no issues. Exact settings. Unpaired, factory reset on phone and watch nothing worked.

  131. Max

    Still an issue. As of today my Fenix 6 does not pickup any GPS signal. CPE shows as current…

  132. Lesley

    Would this affect a Forerunner 230? I went out for a run yesterday, first time since Christmas, and my mileage was .6 miles off compared to Map My Run. And when I go to settings, there’s no CPE listed. Granted the 230 is an older model, but I hadn’t had issues like this before.

  133. Charlie

    My 630 has been dropping miles over the last week or so too. I wonder whether a Garmin update to recalibrate for the Sony chips has now affected those with the older chip? It’s pretty useless. Today’s run had my total running time as 50mins, but time elapsed as 1hr10m – that’s BS

  134. Richard

    Had this issue again today on an Edge 830. I haven’t been out on my bike since before NY but have been using it on indoor mode with the turbo. Noticed the track was way off the road for the first 3 miles. In the end, I stopped in open ground, fired up my Vivo active (which knew where it was because I use it for wandering around the village). After a couple of mins the edge found itself but it is quite annoying.

    I had it when the Edge was new a few months ago when I nipped round to my mum’s half a mile away and got a shifted track but it has been OK since then, until today.

    Could do with a rule that says if it hasn’t been used in a couple of weeks, blow any cache data and get a hard fix. My old Quest might take 5 minutes to get a fix, but it is generally a good one when it does.

  135. Lars

    I had an issue when this first started and just had it again on the evening of 1/25/21. It looks like it started in the wrong place, shifted a couple more times, then eventually locked on the correct location. It is quite frustrating that this is the second time in a month that this has happened. I always wait until a solid lock on my Fenix 6 Pro. I never had this issue with my Fenix 5.

  136. Lysbeth

    As of 26th Jan here were NO real gps issues with the garmin edge 520 for years. (Personally) Just a illustration below in the tracking. Did the things like having the latest update versions, laying it outside for an hour with, and without started activity and riding outside a couple of times.

  137. Deepak Rao

    Well, had this issue on 1st or 2nd Jan, and then it got resolved, but had an absolutely similar issue today on 2 runs. Anyone faced it again?

  138. Will

    Has this issue returned? Noticing quite a few offset GPS traces today.

  139. Bruce

    Appears to be happening again as of today, Feb 10th, Garmin Instinct Solar.

  140. Moo Trail

    This just happened to my Huawei Band 4 Pro. An out and back bike trip along the coast, where my starting leg was out to sea. I thought maybe a reflection error, but now I know, thanks. I was bit bummed because the GPS chip and optical sensor in the B4P is way more accurate than my X40 from a few years ago. Eyes, map, GPS is the rule to remember.

  141. GEORGIOS NIKOLOPOULOS

    FIFY “See…just when you thought you escaped 2000”

  142. Robert Stover

    Gamins New North American & Canada Maps have a voice command Find error ,, find place, find location etc. ALL say this feature isa not available in American English. Speak the name of a place.

    GARMIN FIX this ISSUE !!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  143. Mauro

    Hi DC, looking for an advice, I’ve got my Garmin Fenix 6x,
    CPE shows current, my settings are recording every second/ gps+glonnas / 3D speed and distance activated / soaked GPS for about 10 min before I start my run.
    With all of that, my distance its about half of the real one, pace totally nonsense, etc. Tested for several runs and still the same…
    What can I do ?? just through it the bin ? I’m super frustrated and currently training on my old devices.
    Thanks a lot in advance !!