Routing differences..

[wlepse]

While I was expecting my old TTOne to pick a different route than my new XXL530S, I was not expecting TT's online route to be different than the 530S. I think I prefer the online routing but don't know which to trust or have any idea why they would be different. Just to be clear unit was updated to latest maps and has map share corrections turned on but at high level. Any ideas? Oh and is there an easy way to clear the route?

 

[dhn]

The 530 uses IQ routing. The online planner does not. I'd trust the unit's routing.

 

[wlepse]

I thought online did too, that is why I thought they were asking the time you were planning on leaving?? I had set both to leave right away and still got different routing. I guess I will have to play around a little more around home to get a better feel for it and trust the routings it picks. Out of curiosity, if you plan a long trip (700+ miles) and get delayed during the trip will it recalculate the route automatically since you will now be going through areass at different times? If not how do I force a recalculate without forcing a rerouting?

 

[canderson]

The 530 uses IQ routing. The online planner does not. I'd trust the unit's routing.

I'm surprised to hear that, too, and for the same reason. Why else would they request departure time information, and why would selecting different departure days and times for departure change the arrival times (and sometimes the routing)?

 

[dhn]

They may have changed then. Haven't checked the site in a while.

 

[canderson]

They may have changed then. Haven't checked the site in a while.

I hadn't checked it in eons, either, but had occasion to do so about a week ago when my 8 yr old grandson announced that he wanted to take a land vacation this year and see Mt. Rushmore. Got to fiddling with the site then since the 740 was in the car, and I was in the office, and I figured I'd give the site planner a look and dialed up a couple of different future departure times - and found that the elapsed time was varying. I'm unable to account for that in any way apart from something like IQR data showing up in the calculations somewhere.

Am pondering whether I might eventually select "shorter" instead of "faster" for the first time due to the lousy mpg of a motor home and the current price of gas/petrol.

 

[wlepse]

Now I am confused...I tried the website routing at several different times, taking into account traffic and still no change in the routing. Again the website comes up with a routing similar to what I would have done or google maps comes up with. So maybe it doesn't use IQ routes. I then repeated the trip on the unit and now it shows the expected route so I guess I should just trust the units routing.

 

[canderson]

Now I am confused...I tried the website routing at several different times, taking into account traffic and still no change in the routing. Again the website comes up with a routing similar to what I would have done or google maps comes up with.

Out of curiosity, does it come up with different trip duration when you vary the departure time, even if it does not vary the routing? I find that for many longer trips, the most direct routing winds up being used no matter what -- only in the event of some tricky stuff in metro areas along the way will time of day or day of week change things for that kind of trip.

 

[wlepse]

OK so after running this routing several times all different times of the day I have gotten both the website and unit to give the same two options. Both do vary the time and mileage with each routing. What is a little strange is the other night the website gave routing A and unit B, tonight it is the opposite. The only thing I can think of is that both are using IQ routes but maybe the website is also using live traffic??

OK...back to confused. Just ran the same trip for Friday at 7:30pm and I get different routes. Unit was just updated this morning so I don't think it is an IQ routes thing.