It's my understanding that a navtraffic subscription grants you access to whatever traffic info. is available in your market through XM.

If you live in a remote area with no major highways, there may not be any traffic data to receive.

I'm flustered because there is clearly traffic data available in my area that is not showing up in the car. XM's own website has a map with live traffic info. that has more information in my area than the PCM shows in the car. Also, the State of Connecticut DOT website has more info. as well.

Sirius real time traffic works very well in BMWs. It must utilize local traffic data more effectively whereas the XM Navtraffic seems to be only fully functional in heavily populated urban areas (Metro NY, Boston), which is ironic since the nav. signal in cities can get very weak and compromise route recalculation speeds.

If there is a bad motor vehicle accident in my area (Hartford, CT) that stops traffic completely, it's not showing up on my nav, nor do construction delays, road closings or rush hour traffic.

I called XM and they had me reset my sat radio. That did nothing. I just figured I'd mention this in the event that anyone has experienced this problem. My guess is that Navtraffic is probably useless in over 98% of American cities. There are over 10,000 cities by definition and I'd be surprised if more than 3-4 cities per state on average have full traffic coverage. Take my case for example: there are only 3 states with higher population density than Connecticut. We have essentially 6 active cities, and of those only Stamford, CT has full traffic coverage as its the closest to NY (not much motor vehicle traffic in Stamford aside from I-95 as its a NY bedroom community with many residents riding the train to work).

Bottom line. XM itself need to 'subscribe' and provide more traffic data. Unlike the superior Sirius service in BMWs, its not free.

Are people in other models experiencing this as well? I have an 09' carrera, but I thought PCM 3.0 is the same system in the boxster, cayman, pana, cayenne and 997.2?

-David

Regards,
David

 

Yes, I am finding it not so reliable - better to tune into their traffic/weather station and "listen" - which is actually fairly current and useful - although limited to a handful of major cities. I was hoping the "mapped" data would be as timely and similar. Oh well - better improve or I probably won't renew.

 

The XM Navtraffic data that is overlayed on the map and the incident list in the INFO-Traffic Messages window all come from Navteq, as the data provider. BMW almost certainly has a similar 3rd party provider of its data, as they would be foolish to run their own national data aggregation service... and for the data to get to your car, its got to use some radio reciever - be it FM, XM/Sirius, or cellular. I'm not sure what other providers are out there.. if you could find out what data provider BMW systems use, that would be great.

The data, that is provided for any region, is very much region dependant. The congestion data is frequently driven by any congestion data provided for the region.. if the region doesn't have congestion data.. say thier highways are not instrumented or the local DOT doesn't have some other way of generating flow data, then there isn't anything to overlay on the map. Incident data, however, should still be provided, as everywere I can think of has police provided bulletins about incidents.

If you have a BMW that is getting usefull data on the map or incident listing, and the Porsche is not, when in the same spot, then I'd be very interested in knowing who the BMW data provider is.

That said, XM Navtraffic is still woefully inadequate in displaying timely data.. to many mornings I get the PCM3 displaying green accross all of I-90 and then get on the interstate to see traffic is occasionally stop or 10-20mph (red in my book) and go or going 55-50mph in a 60mph zone (yellow in my book).

There is limited bandwidth that XM has to work with to send the data down, so you cannot get a 100% live stream instantly from every data source in the country (if each county had its own data stream). But not all data is relevant. I'm sure more than 2 satellites provide coverage for the lower 48, so east cost data doesn't need to be send down from central, mountain, or west cost positioned satellites, as an example. But still, there's likely no room for every town to be able to get its flow data up... so they need to focus on the larger metro areas with the most drivers... I can understand that. But for incident data, I'd think they could provide that for ever source (police dept) in the country. The problem is, how to reliably get the data from the sources (police/municipalities) up to the XM offices, and then formatted to send out on the uplink to the satellites. That is a daunting data integration/fusion task... so I've got some sympathy. But in areas where they are providing data, they better sure as hell get the data correct and out in a relatively timely (within 5 minutes) fashion.

 

In-car traffic is in it's infancy no matter which system you use. This is why I didn't bother ordering it in my car. Here's something I can suggest that works for me and is free to anyone with internet access. Google maps has, in my opinion, an excellent traffic layer. If your commute isn't too long simply check it before you leave. If you have a web enabled cell phone such as a "crackberry" or iPhone you can access it in your car. I find the Google maps traffic layer to be surprisingly accurate for my area here in the NY/NJ metro area.

 

Here's the sour pill - BMW uses Navteq same as Porsche. I emailed Navteq and they passed the buck and told me to talk to my dealer.

So either the BMW receiver is superior, or Sirius has better bandwith/broadcast ability.

Like fellow board member Auto-Union, I wouldn't pay for live traffic data. But then it came in my last 2 BMWs for FREE!!!! And it saved me on many occasions. So I opted to pay the monthly fee with XM for the service in the 911 and its nearly useless.

This is regrettably a case of apples to apples comparison and the Porsche (or its XM host) looses dearly - at least in my market.

I think the solution lies in XM steeping it up a bit. Don't forget there were two satellite companies now merged into one. Two traffic nav systems and respective development budgets now merged into one. I'll cut them some slack at present but I want to know that things will improve in my market sooner than later.

 

i've had xm traffic for 3 years - and seattle's had online traffic for 2-3x that. i wouldn't consider that infancy in the technology pov since it's pretty simple from a data perspective.

that said, XM traffic really sucks. i understand the radio frequency traffic is much better than the satellite-delivered traffic but i've never had the thing work well.

EDIT: my XM traffic module is an alpine unit, in my other car, not OEM, for what it's worth

IMO the advantage to having the overlay is to get it real time and be able to use detour software to help you out. if you have a commute that's more than 20 minutes and you are in peak traffic periods, it's likely that an accident could happen while you're already in the car as opposed to when you're still in your office/home.

 

iPhone + velcro tape = best in car nav system

 

+1 thanks for clearly stating the intended benefit of the traffic service. Just yesterday I was with my wife in her X5 and she got off the highway at an exit far in advance of our destination. I was perplexed until the exit ramp raised us up over the highway (I-91 south) and about a 1/2 mile up the highway had come to a full stop. My wife was simply following the nav... Had I been in the Porsche, I would have sitting in the traffic (and paying for the non-warning!!)

Interesting, as I noted in my post, the traffic info in the BMW is very fast to update and very comprehensive. I also noticed in the idrive menu that you can select Auto traffic channel, or traffic channel 1, 2, 3 etc.. There is no such option in the Porsche with XM. I wonder if this this because the XM is satellite based whereas the BMW might be the radio frequency variety you mentioned in your reply?

Either way, XM needs to step it up.

Thanks for the replies.
DRP

 

Gents I've done some research and cleared up the confusion.

BMW uses Clear Channel for its RTTI traffic info. Their maps are from Navteq, but the live traffic information comes from Clear Channel, the only real competitor to XM NavTraffic in the U.S.

What smells a bit funky to me is this - Germany is the longest standing advocate of traffic info. with FREE state funded RDS-TMC since 1997. Guess what technology BMW chose for its U.S. based RTTI system? Yes, RDS-TMC, the same technology as in Germany which is only offered in the U.S. by Clear Channel. So...why did Porsche choose XM Navtraffic (which btw is not in its infancy as it's been available since 2004)? I understand domestic manufacturers sticking with XM, but not Porsche....? Oh well. Maybe XM will improve in time.

Thanks for the responses
DRP

 

Ah, that starts to clear up why there is such a difference.

For me the benefit of the integrated factory solution (as opposed to the ghetto velcro/cradle and an ipod/smartphone system) is that with the integrated factory solution, its got my cars position relative to the traffic by real GPS (not cell tower triangulation pseudo-gps), and the system can update my nav directions on the fly as the condidtions change. I've seen that in action as the car changed which of the 2 bridges it was routing me onto to cross Lake Washington... 520 backed up, as it does predictably, and the routing recomputed and sent me to I-90.

As you note, RDS-TMC is an FM Radio broadcast system, that is locally originated, so you will probably get quicker updates, but also have to push less data through the pipe, since you only address the range of the broadcast tower. XM or Sirius, use the satellite network, which is, national in coverage.

That may be why Porsche offers the XM Navtraffic solution; while RDS-TMC via clearchannel appears to be a better solution, it only works in the very limited number of markets that offer RDS broadcasters. I would be willing to bet that those are only available in a tiny part of the US, such as up where you are. So getting coverage for all regions that have traffic data to publish requires much more work with local broadcasters if using RDDS (the US std for RDS) vs XM.


After looking at the Seattle area XM Navtraffic data a bit more closely in the previous 2 rainy commutes where there was congestion... well, looking at what is rendered on the display, not the underlying data, it appears the Porsche/XM Navtraffic solution is a bit of in when it colors things. Looking at the 'info-traffic messages' list, I saw that RED seemed to be the color of traffic moving at 10mph, and YELLOW was the color of traffic moving at 20mph. So if thats what colors the map, thats really an almost useless thing for highway travel. IE if I'm driving an interstate with a posted limit of 60mph, then a speed of 20mph is as good as a speed of 5mph... its stop and go. Ok, that could be red.

But what is needed is not just coding the roads by the speed of traffic on them (if thats whats happening, as it appeared to be) but how traffic speed differs from the roads posted limit. If the posted speed is 60mph, I'd mark as yellow anything under 45mph, and red anything under 20mph. You need to divide the speed range (0-60 in this case) into fractional regions and color that way. I don't think thats what the Porsche/XM Navtraffic system does. That could be because the NavTeq data doesn't contain info on the speed limits on the road segments, or if the software on the PCM just doesn't interpret the data and use it in the most intelligent fashion.

So for my, the biggest beef I have with the system (in the Seattle area) is the color coding kicks in at too slow of a speed. When the 60mph interstates slow to 45 or even 35, they are still showing up as all green on the map overlay but at that point, I'd rather take the parallel surface streets that run at 30-35mph.

 

XM is desperate in these times, im guessing thats why they dont pay/subscribe/provide more traffic info..

i get calls every week it seems them begging me to come back for even as low as 3$/mon was the final offer!

 

Everyone in radio based media seems to be struggling. Clear Channel Communications is rebounding from their disastrous consolidation of over 10,000 local radio stations nationwide which generated tremendous profit until the consumer became bored with the prepackaged programming they were using in every market - after firing the local talent. And XM as we know is one step away from a bankruptcy filing.

I'm not an advocate of regulation in general and even less of a fan of restricting individual liberties, but i think that some government in the first world (doesn't have to be ours) should mandate certain in car technology with the primary focus on regulating cellular calls and texting. And if they do that, why not mandate free traffic info. You could argue that traffic avoidance ultimately translates to a small savings in government expenditures? Hasn't anyone noticed that everything from a car to a motorcycle to a big wheel now seems to come with tire pressure sensors? It's because its required by law (not sure which one to be honest). Requiring tire pressure sensors is clearly a safety measure, and your could argue so too is avoiding traffic.

P.S. Could you imagine how upset some would be if your car restricted all calls to bluetooth handsfree and disabled texting while the ignition was on.

Something needs to be done about it. My suggestion of raising the speed limits to increase the need for driver concentration doesn't seem to be gaining any momentum

DRP

 

Because the FM transmission based solutions that would be free are not available but in a small handfull of areas of the country.