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Calculation Mode Problems

I had a Garmin Nuvi that I used for many years until the LCD went. Never had any problems with directions. With my newer one, the Garmin Nuvi 55LM, there seems to be an issue with the Calculation Mode. And yes, I have done file updates. I do a lot of traveling in small towns of New England, and the Nuvi leads me down some incredibly poor roads. Have tried all the Calc modes, and still can't get the issue resolved.

Specifically, it brings me down many dirt roads, private roads, class 4 roads (not maintained), and one lane dirt roads, even though they are often longer distances than the preferred route. So I've reverted to always getting directions on Google Maps, which almost always seem to work, and use the GPS only in "View Map" mode.

I'm pretty sure I know what the problem is. Roads in at least some of the states here that are not specifically marked with a speed limit have, by default, a speed limit of 50. I believe this is programmed into the Nuvi, which would be flawed if providing directions based on that. Some of these roads that I have been lead through are so bad you can't even go 5 mph. On several of the class 4 roads the Nuvi has brought me on, I have had to turn around because they are impassable. I wish the Nuvi had a Calculation Mode for "Use Google Maps". Or if it was able to identify unpaved roads, with an option to bypass them, that would help.

Any suggestions? Again, I have tried "shortest distance" and "fastest times", but neither of them work as well as Google Maps. Thanks.

Comments

  • Boyd 1985 Points
    Don't you have the option to avoid unpaved roads? Menus are different, but typically it would be something like Settings > Navigation > Avoidances > Unpaved Roads.

    If you have already done this, then the roads may not be correctly identified on the map, and then you're out of luck. Or if these are paved roads but in poor condition, I guess that would be a problem.

    But I'm a little surprised. I live in a very rural area with lots of unpaved roads and lots of small paved roads. My Nuvis (and also the iPhone StreetPilot app) are VERY reluctant to route me on small paved roads. And these are roads in good condition that are often much shorter alternatives. But the Nuvi just won't use them in a route. When I go down one and it recalculates, it almost always acknowledges a quicker arrival time too.

    With the unpaved road option checked, it has almost never sent me off the pavement.
  • Dave_T 0 Points
    Thanks for your response. I never heard of the Unpaved Road option, so just went out and turned on my Garmin. Yes, I have that option, but it is checked (On) by default. So as you say, these roads must not be identified as unpaved. That really sucks. A few months ago it lead me over a dirt road on a hill that was about 3 miles long and one lane, with no room to pass anywhere. When I got near the top, I came on to another car going in the opposite direction. He had to back up over a mile to let me by. Just last week going to a location, it brought me on a marked privately owned one lane road that was all muddy and with rocks about a foot high everywhere. I bottomed out once in my SUV. On that same trip it brought me on a class 4 road for 2 miles, and the road looked like it had previously been washed out by a stream. There were grooves about 1.5 feet deep all over. I had previously been to this location via a route from Google, but that was also on a dirt road. However it was a decent road. Google had picked this as the default route, as opposed to the other one I took, even though it was a few miles longer. So I had to go there again a couple of weeks later, and figured I would go by the Garmin route, and it took me the way listed above.

    I have no idea why I'm having all sorts of problems with unpaved roads, and you aren't. These trips I'm talking about are in NH and VT. I've also found similar problems on paved roads, and have already figured out that is because speed limits often shown on the Garmin are wrong, so route calculations are going to be incorrect.

    If Google Maps can do this right, then Google has better road information than Garmin. Why can't Garmin get better data? I'm new to this forum. Is it monitored at all by Garmin support? I would like to get a response from them as well. Thanks.
  • alanb 539 Points
    edited October 2016
    Could you give us an example of a route (start point and destination) that routes you over these dirt and unpaved roads? With that we could check it on our devices to see if we get the same results or if it is some kind of failure in your device, maps, settings, etc.
  • Boyd 1985 Points
    edited October 2016
    This forum has absolutely no affiliation with Garmin or any other company. It is a user to user forum. While Garmin employees might read it, they have never posted a response here. You can contact Garmin support here: http://www.garmin.com/us/support/contact?#fragment-1

    Comparing Google to Garmin is apples and oranges. The nuvi is a wimpy little computer with very little storage and a processor that's generations behind modern smartphones. Google uses powerful servers and a huge map database that is constantly being updated, your computer or smartphone is merely a terminal to access this powerful system as opposed to a self-contained device like the Nuvi.

    Google uses their own proprietary map data (have you ever seen those "Google cars" with cameras on the roof?). Garmin purchases map data from a company called "Here" (formerly known as Navteq).

    If you really prefer Google, then a smartphone with their app will be a better solution. Can you still return your Nuvi and get a refund?
  • Dave_T 0 Points
    alanb said:

    Could you give us an example of a route (start point and destination) that routes you over these dirt and unpaved roads? With that we could check it on our devices to see if we get the same results or if it is some kind of failure in your device, maps, settings, etc.

    Sure, the trip above that brought me over a private road and an almost impassable class 4 road was from Littleton, NH to a hiking trailhead at 3167 Coits Pond Rd., Cabot, VT. Google gives you 3 routes, all of which are fine. They all approach the destination from the south on Coits Pond Road. The Garmin brought me to Coits Pond Road from the north, via Corner Road and Houston Hill Rd.

    Note that all of Coits Pond Rd is unpaved, as are the other 2 roads I mentioned. Also note that Google does show Corner Road and Houston Hill Rd, as would be expected, but does not even show this as one of the possible routes to the destination.
  • Zemartelo 207 Points
    My 2597 nuvi calculates that route thru I93 then to I91 and get on route 2 passing Danville to turn to Danville Hill rd towards Cabot to Hwy 215 and then turn to S Walden Rd and turn to Houston Hill rd and finally get to Coits Pobd Rd. This is with the avoidance unpaved roads unchecked.
    With that option checked then from route 2 it turn to hwy 15 towards walden twn and turn to route 215 N and turn to S walden rd before getting to Cabot.
  • Dave_T 0 Points
    Zemartelo said:

    My 2597 nuvi calculates that route thru I93 then to I91 and get on route 2 passing Danville to turn to Danville Hill rd towards Cabot to Hwy 215 and then turn to S Walden Rd and turn to Houston Hill rd and finally get to Coits Pobd Rd. This is with the avoidance unpaved roads unchecked.
    With that option checked then from route 2 it turn to hwy 15 towards walden twn and turn to route 215 N and turn to S walden rd before getting to Cabot.

    Thanks. That is exactly how I would have expected the directions to be for both Unpaved Roads checked and Unpaved Roads unchecked. Both of those routes approach the destination from the south. The route I am getting with the Garmin, with the Avoid Unpaved checked, is approaching the destination on 3167 Coits Pond Rd from the north, via Corner Rd and Houston Hill Road. That route, which is the one with an impassible class 4 road and a private property road, is not even shown as a possible route on Google. It must be a combination of settings that is causing the problem. I'll have to look at it more closely.
  • sussamb 813 Points
    edited October 2016
    If you haven't done one recently you may find a master reset will help. I've seen strange routing issues on some units resolved after a reset.
  • Boyd 1985 Points
    Didn't one of the recent map updates cause strange routing problems on certain Nuvi models?

    BTW, hard reset instructions are here if needed: http://forums.gpsreview.net/discussion/21511/x/p1/
  • sussamb 813 Points
    Well one gave a problem with address searching ... Can't recall one giving a routing issue other than the occasional issue on some devices which seem to be cured after a reset, probably because a software update occured at the same time.
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