Anybody from the Mpls area have the Nav Traffic? I just got it, and do not see the speeds on the map. I do have the speed icon turned on, and the zoom is in the correct range. Wondering if its my car, or just not available....

 

Do you have any traffic functionality at all.

What happens when you ask the car for "Traffic Incidents"?

 

Are you still in your free XM promotion period? I didn't get the nav traffic until I took over the subscription.

LL

 

There aren't speeds listed, it is by color code on a road that is covered by Navtraffic.

You'll have to check the manual, but I bellieve the breakout is as follows.

Red = 0-25mph
Yellow = 25mph-50mph
Green > 50mph

That's ballpark, like I said you have to check to verify.

You also need to have the subscription, and you need to make sure you have coverage in your area.

More info here.

http://www.xmradio.com/navtraffic/

 

I got my Traffic from Day one I took the car from the Dealership. Did u check whether MPLS is offering live traffic. Check with XM as some cities are not in their system to provide the Live traffics yet.

 

GoHawks is absolutely correct though the speeds are a little off. Here is a quote from the Nav manual:

Traffic Flow Data
(using bands parallel to the road)
Heavy traffic: 0 – 27 mph
(approx.)
Moderate traffic: 27 – 52 mph
(approx.)
Free flow traffic: 52 + mph
(approx.)
(shown for both sides of the freeway where
available)


The operative phrase is in bold

This is why you should use the voice or menu command for Traffic Incidents to verify you are getting Nav Traffic, and you should have some amount of color coding along major highways, if it is offered. Many times, the city only has incidents, but not the flow information described above.

 

Thanks all for the good info! I did just get the full subscription to both xm radio and nav traffic ($124!) I was under the impression that there would be a numerical mph over the road. It does give the different colors pretty accurately so far!. I only turned it on last nite, so I need to watch it a little to learn the nuances.

 

I'm in SF Bay area. Experience with nav traffic is mixed. Typically there is a significant delay in the update of "real-time" traffic. Depends on the source of the data and they (NavTeq) compile data from vairous sources.
Here's what I have observed:
1. Data is refreshed on Navi screen every 5 minutes
2. Some times the traffic disappears for all or part of the highways during one of these refreshes. Thus speeds are gone for 5 minutes. I assume this is caused by some transmission error between car and satellite or software calc error in Navi
3. Delay between actual speeds and what Nav traffic shows can be 15 minutes up to 45 minutes. I think this is due to how XM and NavTeq communicate, aggregate the data and transmit to car. I have compared to other real time traffic maps on the Web (Google, local radio web site, etc.) and it almost always behind. Not only behind in posting slower speeds, but slower in removing congestion speeds and restoring faster speeds.
4. I actually talked to an Engineer at NavTeq and he said some of the sources are actual vehicles, i.e., gps data and other is road sensors. In some areas, the road sensors are more dense than others. So that in less dense areas, the sensor may "see" slow traffic that is highly localized and display slow speeds for a long stretch of roadway that is not accurate. Then of course, there is the reverse that the sensor does "see" the congestion.

Net/net for me is that it is fun to show people in your car, but to make an actual decision to reroute yourself is difficult to trust. How do you make a decision on 15 minute old data let alone 45 minutes old. You could decide to go well out of your way to avoid congestion that is no longer there. Or, you are stuck in traffic wondering when the so-called "Real-Time" Navtraffic is going to show red instead of blue!

 

Not bad for off the top of my head, huh?

 

I'd say you were (approx.) right on!

 

Damn good, and a lot better than I could do!

 

getakey - I agree a neat toy to show your friends but damn close to worthless in the real world. Another example of: You can snow some people some of the time but you can't snow an RL owner!