I've noticed the system will often give false warnings during a route i.e. Road closed or heavy traffic ahead, when in fact the condition does NOT exist. Anyone else experience this? I'm simply ignoring them at this point but curious if there's a fix.

 

When my NAV has warned me of slow traffic ahead on my route, it was true and would run into slow traffic. I have little to complain about and the NAV system works pretty well for me.

This feature is not a Lexus thing, I think it is a HD radio thing as it tracks traffic and accidents on your route.

 

so if this is a hd radio thing, i'm guessing it needs to be in more dense areas to work ?? or will it works heading down interstates ??
i drive several times per year from minneapolis to arkansas and also to tn/nc smokies area, curious if this would work, guessing i would still be running waze for the added information

thanks

 

I am not sure how the HD radio works. I would like to know how the HD radio knows the traffic has slowed down and where the accidents are. Who reports these accidents and how does the speed of traffic get to the HD radio people?
In Jacksonville, it works well. You can tell from way ahead if the traffic is slowing or even stopped. Accidents are marked on the map and there are times when in NAV mode you actually get a verbal warning of the accident or slow traffic ahead.

Maybe someone here know how this HD radio works.

 

On Thanksgiving I used the nav system (Enform App Suite) and was told slow traffic ahead on your route, there was no slow down, in fact the traffic was unusually light all the way to our destination. I don't know how often that happens.

 

On my last road trip, the NAV warned me for "Stop traffic" and suggested an alt route. So I followed it and went off the highway. Indeed I later saw stop traffic on the highway while driving on the road parallel to the highway.

 

Indeed traffic and weather information is supplied by HD radio. In the event you aren't near an HD station, the Lexus Enform App Suite works as a backup data source for traffic and weather. BTW it has worked fairly well for me.

 

My exact experience. I just ignore it now which isn't great in the event it's accurate. Everything else with the NAV works fine for me.

 

The Lexus USA site states " Denso works with NAVTEQ, Tele Atlas and InfoUSA to gather information for Lexus' navigation updates". Obviously the website is not up to date as the NAVTEQ brand doesn't exist (they changed the name to HERE maps in Nov 2012) and the Tele Atlas brand doesn't exist (they were bought by TomTom years ago). HERE and TomTom are direct and fierce competitors.

Whichever mapping company Lexus uses the method of obtaining traffic information is the same. The mapping company gathers information from numerous sources like government agencies, road sensors and GPS plot points from vehicles on the road. This information is processed and it can be determined how fast traffic is moving and where bottlenecks or accidents have occurred. The data is embedded in the HD radio signal. The mapping companies promote the fact that the data is updated every 30 or 60 seconds, however that may not always be the case as they have to process billions of GPS data points every day. Also the HD radio signal is only available in metro areas (mostly) so if HD reception is not available traffic info will not be available.

 

Yes the traffic data is mined from many sources: commercial traffic data providers, departments of transportation, police and emergency services, road sensors, traffic cameras, etc. It is not crowd sourced as Google or Apple Maps. This information is compiled and delivered via radio frequency (FM/HD Radio™ or satellite) to your car.

Having said that, I have seen reports of traffic congestion and route changed, yet no congestion from normal experienced, nor a significant change in route. However, many times a congestion is reported that is accurate. So it seems it highly depends on the timeliness of the data and how well reported in the local city. The system also tries to predict your route, so for significant conmute, the data might be too old by the time you reach the incident.

 

I have found the onboard NAV to be terrible. Recent Thanksgiving trip down and up the I-95/I-85 corridor on Sundays only had all the construction zones shown as slow downs but nobody was working.
Found Waze and my Valentine One to be best.

 

the update is "supposed" to happen every 15 minutes over HD however I have noticed that it doesn't..

the system that provides the data is: http://www.ttwnetwork.com/ (you can check this website for your coverage area)

it is very limited (IMO) to its coverage areas, and it is very slow to update using only the HD connection. if you are running the Enform App on your phone, it will also use your cell service data connection and the updates happen a lot quicker and seem to be more accurate, but it is using a live data connection to the phone/cell service and will eat away at your data plan.