[DrMurano]

Has anybody had a similar experience?

I was driving back from Lake Tahoe and set up my Nav to navigate me back home (well mainly I wanted to know how much time and mileage is left until I get home). Well, I am on a long ~ 100 mile stretch, when all of a sudden the Nav starts telling me that it is re-routing me. I look at the screen and the red arrow is way off the freeway I am traveling on. It kept re-routing me for a few minutes and than went back onto the freeway. I pulled over, turned the car off and after re-starting the car kept on driving. It was fine for a few minutes, and again, the same thing happened. I pulled over again, got the DVD out of the NAV, re-inserted, and drove again. NAV acted up again for a few minutes and then everything went back to place for the remainder of the trip.

Can you guys comment on this? Any suggestions?

 

[pcs15394]

DrMurano

I don't have the factory Nav but had a similar thing happen to me while driving on the Interstate here in Florida. Mine showed that I was on a Side road running Parallel with the Interstate. Took about 20 miles and then straightened itself out.

 

[Ferio]

I have seen that happen when the system loses track of the satts and goes to inertial mode which uses the speed of the vehicle and the compass to approximate where it is. It can also happen when it cannot get enough satts to get a good reading and it loses accuracy.

Since inertial mode is not as accurate it starts guessing. I have had my systems tell me i was driving through mountains, over a lake and one time down a river. Once the navi realigns or gets a good signal then it "finds" where it really is again and properly updates display.

Inertial mode is used for things like tunnels and such. This allows the navi to keep a pretty good idea of where it is during brief loss of signals. I have also seen it lose signal when surrounded by tall buildings and suddenly the system shows me inside a building.

The other thing that commonly happens is when the parallell road is within the accuracy distance of the navi. Then it guesses and can sometimes show you on a parallell road until there is sufficient distance between the points to let it figure out which one is the correct placement.

I am on my third navi and all have the same tendency. Maybe after the EU gets their constellation up we can get better accuracy.

 

[nissanlove]

can someone tell me were to get the navigation cd??

 

[dklanecky1]

can someone tell me were to get the navigation cd??

It's a DVD not a CD, and you can but new ones from Zenrin.com.

 

[Dalite]

Another slim possibility is "Selective Availability" near Military Bases or Strategic Targets.

Homeland Defense has to decide between giving wide-open accuracy, and the chance that our GPS Sats will be used against us in targeting high-impact installations.

I have had a similar problem when routing around a Military Base (Ft Stewart in Georgia).

 

[msfiveiron]

I have a stretch of highway near my house that the nav system consistently misses. The highway has local and express lanes, and the system always thinks I am in the express lane, regardless of which route I choose. It makes some of the directions a PITA if I need one of the turn-offs before the system gets itself straight again. As a result, I've learned to always check the route before pulling out of my driveway if I think that the system will suggest that road. That way, I can take the correct turn-off, knowing that the system will re-correct once it understands I am on the correct route.

 

[Mr3Putt]

Where is the antenna for the factory NAV system? Is there an external one?

 

[dklanecky1]

Where is the antenna for the factory NAV system? Is there an external one?

I believe it's buried up in the center of the front porch (dash).