How does GPS get traffic info?

Satellite radio is equipped to send and receive small amounts of data to a blanket coverage area. This is used for activation (and deactivation) of the receiver, channel updates, preset updates, that sort of thing. They also figured out how to put a little bit of traffic information into the stream as well.

Another route for the update is through the toyota connect. That is a cell style CDMA connection that piggy backs off of Verizon and Sprint antennas. Then you get any sort of data you want, including traffic. Or if you tether your phone to the system, it now can use that as a generic data connection. The cell style data plan is what most hand held GPS units use (like a Garmin).

 

Many dealerships will automatically set you up with a trial subscription to XM, including the traffic data.
I have it as a trial, and honestly, it's not worth paying for, IMO. I find that when I want to know what's going on, there's no incoming data. Other times, it shows it just fine, but when I need it, it's delayed.

The traffic data that Google Maps provides is way more accurate.

 

Agreed. My handheld Garmin has Google Search built in (uses its own internal cell data plan) and uses Google traffic updates. It is for the most part accurate and worth paying for if you routinely drive in heavy traffic. I can make my own hours, so I just leave before or after the "rushes" and then I have no traffic. So I let the 1 year trial lapse. But if I had to commute with everyone else, I would gladly pay for it.

 

Here in California, the Highway Patrol has an incident page which can be accessed via an APP. This is really a great tool to monitor traffic and understand what's is going on. It is all in real time. Knowing where the problems are in real time you can decide to move around it or expect the traffic.

 

Try Waze. The people give updates as they drive. Traffic...radar...accidents..etc. Its free.

 

real time is the only way to go, unless there is a huge accident that is going to block traffic for hours. around here, when they say traffic is stalled, it's usually clear, and vice versa. pretty much terrible info.