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Turn by turn directions not robust and reliable?

Former Member
Former Member over 7 years ago
When Turn by Turn directions are working rigth on my Edge 820, they're quite nice and pretty much all I could ask for. But that's only some of the time. Over the course of my riding so far, I've seen all of the following happen (sometimes on the same ride):

  • A turn saying to turn onto a 'Trail', when in fact I'm turning on to a relatively major street that is on the map.
  • If I'm off course for too long, the Edge will quietly give up on TBT directions even when I rejoin the course. This can generally be cured by ending course following and then restarting the course, but this is a lot of delicate touchscreen tapping when you're moving in a group ride.
  • A moderately perverse route that doubled back on itself at one point seem to cause the Edge 820 to simply give up on TBT from that point onward; not even restarting the route helped.

  • The TBT directions just deciding to redirect me off the route onto something else. Often the 'something else' is very wrong, like when the Edge wanted to send me sideways down an alleyway instead of continuing on the street as the route had plotted, or when it wanted me to turn onto a 'Trail' that didn't exist. When I decline to follow the directions, this can lead the Edge to decide I'm off course and give up on TBT directions even though I'm riding the actual set route.

    (This isn't consistent, either. I recently did two group rides on two successive days that went along the same segment. On the first day, the Edge 820 tried to redirect me off the route; on the second day, it was happy to turn at the route's official turn.)

  • Turn alerts that are actively dangerous and misleading. At several straight-through 4-way intersections I've had the Edge 820 alert for a 90-degree right or left turn when even its map display thought there was only a little jog to one side in the route (and in reality it was straight through). Had I blindly followed the alerts I would have been instantly off course, often turning on to busy roads.


I've had this happen with both RWGPS routes (tcx and gpx) and with routes from Garmin Connect itself, all with (only) the normal Garmin maps. I've seen all of this happen on simple commute rides here in downtown Toronto, which ought to be a well-mapped area (we're not in the US, but it's not like we're obscure). Using an OSM map doesn't seem to make any real improvement in the situation (and using the OSM map alone is a total failure, the Edge 820 seems to really dislike that).

I did enough searching and reading before buying the Edge 820 that I knew that the Garmin Edge series in general wasn't exactly perfect as far as TBT directions went, but this feels excessive (and dangerous). Are these the kind of things that other people are seeing with Edge 820s, or am I having a relatively uniquely bad experience with TBT directions here? Also, are some or many of these things long-standing issues with Garmin Edge units and thus unlikely to be fixed in firmware updates, or do they sound like new problems that might be fixed in the future?

(I cynically assume that if Garmin has had a particular issue over multiple Edge models for years, they're not going to be fixing it this time around either.)

Relatedly, are there any known good (or standard) workarounds for these sorts of issues, like route shapes to avoid, things to do if you know you're going off course, settings to absolutely avoid (I already have all of the recommended RWGPS Garmin Edge navigation settings set), or ways to recover (beyond 'stop the course then reload it')? I'm already having RWGPS include cue sheet entries in the routes I pull from it and checking them, but that's a bandaid.

Since I bought the Edge 820 primarily for navigation, this is really bumming me out. It's a nice unit when it works, but it doesn't work robustly or reliably enough to completely replace paper cue sheets on my group rides (especially if I'm leading the ride and absolutely should not be making navigation mistakes).
  • 0 over 7 years ago
    • A turn saying to turn onto a 'Trail', when in fact I'm turning on to a relatively major street that is on the map.
    • If I'm off course for too long, the Edge will quietly give up on TBT directions even when I rejoin the course. This can generally be cured by ending course following and then restarting the course, but this is a lot of delicate touchscreen tapping when you're moving in a group ride.
    • A moderately perverse route that doubled back on itself at one point seem to cause the Edge 820 to simply give up on TBT from that point onward; not even restarting the route helped.
    • The TBT directions just deciding to redirect me off the route onto something else. Often the 'something else' is very wrong, like when the Edge wanted to send me sideways down an alleyway instead of continuing on the street as the route had plotted, or when it wanted me to turn onto a 'Trail' that didn't exist. When I decline to follow the directions, this can lead the Edge to decide I'm off course and give up on TBT directions even though I'm riding the actual set route.
    • Turn alerts that are actively dangerous and misleading. At several straight-through 4-way intersections I've had the Edge 820 alert for a 90-degree right or left turn when even its map display thought there was only a little jog to one side in the route (and in reality it was straight through). Had I blindly followed the alerts I would have been instantly off course, often turning on to busy roads.

    1. I suspect there is a path (trail in Garmin speak) right next to the road you are planning on taking and it is so close you can't see it on the map screen. Check OSM to see if this is the case. I have had my Edge 800 direct me along pavements next to the road I am on when they have been mapped as separate paths in OSM. I use OSM based maps on it.
    2. Can't help on that one
    3. I have had this with my Edge 800. If you actually take the side turning as instructed you are then immediately directed back on the road you were on before. It is a quirk and I don't know why it happens sometimes.
    4. Does the Edge only have 90° turn symbols? My Edge 800 does something similar. It will say turn left/right when in reality on the map/ground it is just a slight bear left/right. I put that down to the device not having lots of turn options between straight on and a full left/right turn (probably to reduce the difficulty in having that work sensibly). My Edge 800 pops up the map when I need to turn so I can easily check the actual road layout together with the Garmin generated turn notification.
  • 0 over 7 years ago
    Looking at the map carefully it appears that Garmin has mapped the sidewalks and decided to turn on to one of them, despite the route going along the street.

    Garmin haven't mapped anything. The map supplied by Garmin with the 820/1000 is based on OSM data so you can always check on OSM itself to see what features are there and correct any errors. Sidewalk mapping isn't very consistent on OSM though. In some places they are mapped as separate ways (as you have found) and they aren't mapped at all in other areas (most places I have seen).

    Do you (or anyone) know what the consequences of Navigation -> Routing -> Routing Mode settings are, especially the difference between 'Cycling' and 'Tour Cycling'? I've read that you want Tour Cycling in order to include bike paths in routing calculations, but maybe that's wrong?

    The best I can suggest is look at the route planning settings in Basecamp. Compare the different cycling modes. I would assume the versions in the 820 would be similar.
  • 0 over 7 years ago
    • The TBT directions just deciding to redirect me off the route onto something else. Often the 'something else' is very wrong, like when the Edge wanted to send me sideways down an alleyway instead of continuing on the street as the route had plotted, or when it wanted me to turn onto a 'Trail' that didn't exist. When I decline to follow the directions, this can lead the Edge to decide I'm off course and give up on TBT directions even though I'm riding the actual set route.



    I don't have Edge 820. Anyway this resembles somehow my experience with Edge 810: check "Edge 810 fails to assume that there is a parallel trail (1/3)...(3/3)" in https://forums.garmin.com/showthread.php?327348-Firmware-4-32-beta&p=744525#post744525

    EDIT:Possibly Edge 810/820 is too pedantic about tiny differences of road placement on different maps (planning versus riding).
  • 0 over 7 years ago
    When Turn by Turn directions are working rigth on my Edge 820, they're quite nice and pretty much all I could ask for. But that's only some of the time. Over the course of my riding so far, I've seen all of the following happen (sometimes on the same ride):

    • A turn saying to turn onto a 'Trail', when in fact I'm turning on to a relatively major street that is on the map.
    • If I'm off course for too long, the Edge will quietly give up on TBT directions even when I rejoin the course. This can generally be cured by ending course following and then restarting the course, but this is a lot of delicate touchscreen tapping when you're moving in a group ride.


    I used the nav on the 820 yesterday perfectly for more than 4 hours. 4 hours of navigational perfectness. I really couldn't have asked for more. Unfortunately the ride was over 8 hours long.

    Yes I lost the tbt as you describe and the only way was to reload the course. I was following a 120km course which took a looooooong time to reload (5 mins??). Once when I reloaded it I made a turn and ended up speeding off-route 3 k down a towpath. enjoyed the detour so much that I ignored the 'off course' message when it finally popped up. #achylegs
  • 0 over 7 years ago
    I've had this happen with both RWGPS routes (tcx and gpx) and with routes from Garmin Connect itself, all with (only) the normal Garmin maps. I've seen all of this happen on simple commute rides here in downtown Toronto, which ought to be a well-mapped area (we're not in the US, but it's not like we're obscure).


    There is is no magic in particular route planners and there is no magic in the file format. Every route planner does the same thing and tcx/gpx files are equivalent.


    Using an OSM map doesn't seem to make any real improvement in the situation (and using the OSM map alone is a total failure, the Edge 820 seems to really dislike that).

    This doesn't appear to make sense.

    Anyway, the normal Garmin maps (the maps that come with the unit) are OSM maps.

    I didn't have 'lock on road' set on, because a number of my bike club's routes go along paths, but maybe this was screwing it up.

    No. The "lock on road" only changes where the location cursor is drawn (it's a display feature).

    IDo you (or anyone) know what the consequences of Navigation -> Routing -> Routing Mode settings are, especially the difference between 'Cycling' and 'Tour Cycling'? I've read that you want Tour Cycling in order to include bike paths in routing calculations, but maybe that's wrong?

    Those have no effect on loaded courses. (It would defeat the purpose of using a course.)

    They do, obviously, effect on-device routing.

    The Edge 820 seems to have a relatively varied collection of direction symbols for alerts. I've certainly seen it signal a more than 90 degree turn (at a spot where this was correct; we were on a bike path and turning sharply to another path that climbed up a hill). Maybe it doesn't have a symbol for a right-left jog.

    Aren't you seeing big white arrows? There isn't a "collection" of those. They just are drawing the route through the turn with a really wide line (and adding an arrow at the end if it).

    If you are seeing little icons with short labels, those are "course points" from the tcx file.)

    Unfortunately the 820 doesn't have any option to switch to the map screen when a turn is coming up; it stays firmly on whatever screen you're currently on and you must manually swipe over. That's part of what makes this so dangerous, since you have to remember to do this and swiping over isn't necessarily easy or fast. Don't have time to look carefully and whoops, you just turned off the route into a busy street where you can't easily get out.


    With "turn guidance" enabled, you get big white arrows and (on the 800 and other units), the screen flips to the map before the turn.

    Anyway, if you are in a complicated navigational situation, keeping the map screen on will make navigation more reliable.
  • 0 over 7 years ago
    ... The "lock on road" only changes where the location cursor is drawn (it's a display feature)...


    On my previous Edges it affected my activity data. At times the recorded activity showed me hopping back and forth between my actual position and a nearby road when I deviated from the course through a parking lot or path.
  • 0 over 7 years ago
    On my previous Edges it affected my activity data. At times the recorded activity showed me hopping back and forth between my actual position and a nearby road when I deviated from the course through a parking lot or path.

    It doesn't do that on the 800.

    It makes no sense, at all, to work that way. It would be really dumb to do.

    It would be so stupid that there would be many, many complaints about it. Yet, I've never seen any mention of it (other than your one comment here).
  • 0 over 7 years ago
    This makes me wish that the Edge 820 gave you some way to have decent control of what sort of things it used for routing, but alas the controls available are what you could call 'very minimal' and not very informative about what exactly they control.

    If you are using a course, you are selecting the roads/paths you want to use. You have 100% control over the routing when creating a course/route.

    Keep in mind that the gpx/tcx file just contains a list of points. There is no information about roads in the tile.

    That means the Garmin have to figure out what roads/paths your list of points appears to be using.

    That's what it is dong when "calculating" appears on the screen.

    For this to work "perfectly", the map on the device have to be the same as the map used to plan the route (both using OSM maps, for instance).

    For different maps, the placement for roads an paths are often (slightly) different. If there are two roads/paths close together, which of the two is selected as what it figures you intended to use is random.

    That is, that side paths are sometimes chosen over the road you want is expected.
  • 0 over 7 years ago
    This is what I expected, but I'm a system administrator so I believe in testing this stuff (and then mentioning it, just in case). Also, Product Support seems more willing to talk to me about routes from Garmin Connect than routes from elsewhere.

    You can look at the files (they are just XML files). People have all sorts of notions. It's important to be clear about how things work (and you aren't the only person reading this).

    The arrows I'm talking about are the ones in the turn alerts you get if you're on non-map screens, or more specifically for TBT turn alerts, where I've seen a wide variety of symbols. I don't know if the 820 has a (big) set of them or if it just draws them from scratch based on the big white arrows it draws on the actual map, but given that I've seen mismatches between the alert arrows and the map arrows I suspect that it has a stock set.

    Tcx files have "course points". These are waypoints that get displayed when you get close to them. There is a small icon and a very short label. There's a limited number of icons. "Course points" are how units without maps can provide very-basic turn instructions.

    The mapping units provide a second type of turn instruction Garmin calls "Turn Guidance". That uses big white arrows and those are dynamic (drawn from scratch) since they follow the turns exactly. They sometime follow complicated quick twisty turns.

    I'm not in what I consider a complicated navigation situation. Almost all of the routes I've seen problems on are very simple, with only infrequent turns and everything on roads. But my Edge 820 apparently disagrees with me about what is and isn't complicated, and will turn what I think is a simple route into something else. This makes it extremely difficult to predict when I need to keep a close eye on things, and I don't want to have to be on the map screen all the time (or even to try to swipe over to it every time the Edge starts talking about a turn).

    I'm not quite sure what problems you are having. My goal is to try to convey how the devices work.

    The issue you describe about side paths is something I'd expect (based on how the devices work). The maps shouldn't have sidewalks. People probably want the maps to have cycleways but the device is often going to be confused when they are right next to roads.

    I bought my 800 (all the units basically work the same) for navigation. So, I don't have an issue with having the map displayed. While I understand that some people don't want to do that but it does make navigation more reliable.
  • 0 over 7 years ago
    In theory I have 100% control.

    You have 100% control in designing the route (that's not theoretical).

    The devices can have issues following the course as you intend but those issues are not the result of the device picking "better" roads. The issues are more the result of inaccuracies.

    In practice the 820's turn by turn directions will sometimes expressly divert from the route (and significantly) despite clearly knowing that the route goes down a street. One case on my commute ride is striking; the route goes straight down a street, but the 820 wants to go left at an intersection, over to and down a parallel 'Service Road' (an alleyway), then later turn right off the 'Service Road' and back over to the street the route is going down. And if I actually start riding this diversion, the 820 immediately alerts that I'm off course.

    That's probably the "shortcut" problem. Sometimes, the devices pick a shortcut instead of following the course. It's related, probably, to how the device was the track to find the nearby roads.

    https://forums.garmin.com/showthread.php?173089-The-planned-course-is-not-respected&p=451145#post451145

    You probably get two purple lines when that happens.

    https://forums.garmin.com/showthread.php?83969-Thick-pink-line-on-map&p=290519#post290519

    The "off course warning" is based being to far away from the gpx track.

    On some of the units, you can choose to get just "off course warnings" without any turn guidance.

    The other problem is that as I mentioned in passing, I seem to be doing something wrong with OSM maps so that at best they're ineffective.

    I use the OSM maps routinely. The Garmin maps are OSM maps.

    Having this map enabled along side the others doesn't seem to have changed my 820's odd routing decisions and behaviors (although it does seem to slow down the 'calculating' phase), even on routes where I've specifically created a RWGPS .tcx using RWGPS's 'OSM Cycling' map option instead of the default. I made a few attempts to use only the OSM map alone, but that seemed to cause the 820's TBT stuff to mostly give up and not give me turn information. So I expect I'm missing something or doing something wrong here.

    Maps have two sets of data: image data (the stuff you see on the display) and routing data (the road network info used to generate routes). You can't really have more than one map covering the same region enabled at the same time. (Maps can be designed to overlay image data.)

    I've had (and have) two problems here. The pragmatic problem is that I got my 820 for bike club rides and the bike club has standardized on building its routes using RWGPS with the standard Google Maps based map. If these don't work well on the 820, at best I get to make a RWGPS copy of the route for every club ride I plan to do, change the map type to OSM Cycling, poke the map so RWGPS re-lays out all of the points to follow the OSM version of the roads and so on, and then use that version. (I wish there was a way to tell RWGPS 're-snap everything to roads and paths on this new map', but there doesn't seem to be.)

    You could do that and things might work a bit better. I don't find a need to do that on the 800. I know how the devices work and I keep an eye on the map. With that, I don't really have difficulty dealing with the infrequent navigation issues

    It's possible that the new 820 has more bugs than older units. I'd be reluctant to give up my 800, which seems fairly reliable for navigation.