Navigation System one block off in Manhattan
The few times I have been to Manhattan it was difficult enough for me to see daylight...and it will definitely be difficult for a nav system to see satelites..the buildings there black anything from above and the number of received satelites will definitely be a lot less then anywhere yway from the skycrapers.
greetingz,
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Last edited by Barry45RPM; Aug 1, 2004 at 07:33 PM.
MB Manhattan did say that sometimes the govt does co-opt the satellites for security reasons leading to NAV being incorrect in manhattan. According to them, this problem does not exist off the island. That is consistent with my experience, it never faltered outside manhattan.
Even if I setup for directions, and let's say I have to make a left turn on a street and I'm waiting (first car) at the light to make the left (i.e. I'm at the intersection), the Nav guidance shows 50 feet to the left turn point.
Dealer is looking into this right now since my car is with him for other problems. I will let you know the result...
I have not, nor do I know of, any sort of calibration that can be done, as this is done automatically. Back a while ago when it was extremely off by a couple hundred feet for me, I ended up pulling the fuses for the entire COMAND system, and that seemed to work (at least it returned me to the 50 feet off situation). When I took it to the dealer last to be fixed, they could not remedy it.
It really is amazing that the car can use its current speed and direction to determine its position when no satellite data is not availalbe, although it is prone to error. Perhaps what you are experiencing is the NAV relying on the "calculated" position (because of blocked signal because of skyscrapers) based on your current speed and direction, and the last satellite contact.
It really is amazing that the car can use its current speed and direction to determine its position when no satellite data is not availalbe, although it is prone to error.
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Probably the DVD in your drive was mapped & published before the tunnel & rerouted streets were added to the database. A nav update should solve the problem
http://www.boston.com/travel/article...g_dig_muddles/
"The devices direct you to your destination using sophisticated mapping software and global positioning system, or GPS, technology. The systems are vastly superior to the minimalist maps the rental car companies hand out, but they have limited effectiveness in downtown Boston, where tall buildings and extensive underground tunnels block GPS signals and Big Dig construction alters street maps almost daily.
''Boston is the only city in the country with all [those] three factors at work. It's unique," said Pat Ray, business development director for Hertz's NeverLost. ''Boston is the toughest test to put a navigation system through.""
Good Luck navTech!






