For those of you that have Nav, I need you to check something.
When the map screen is up there is a satellight icon in the top right corner. It is white when NOT receiving a sat signal, yellow when it is receiving a some of the sat signal, and green when locked on 100%.

While driving, my sat icon goes from green to white to yellow to white to green. In other words it is NOT locked on green all the time. My dealer checked, and he says it is normal. I also did the self diagnostic test, it came out fine.

On my hand held GPS units, once I have a lock, it is locked.

I think there is something wrong with my nav. I am "almost" positive when I first got the car, the icon was green 99% of the time while driving. Now it is green maybe 50 to 60%. Plus when I turn on the nav, the Infiniti logo screen *seems* to stay on longer than it did.

Could some of you with nav check the satellight icon while driving and let me know what YOUR icon does while driving.
Thanks in advance!!


BillR

 

I have noticed that the GPS seems to reacquire signal more frequently than I thought it would. When I am driving around, I notice that the Satellite indicator switches between 2D and 3D coordinates (yellow <-> green) more in some areas than others. I put it down to local disturbance. I guess it could be the location of the GPS antenna relative to the car. As for your handheld, the different antenna style and location (your hand) it may have a more constant signal strength.

One thing to ask yourself: "Has the location, of where you drive, changed from where you noticed a full green to partial green satellite indicator?" Or maybe you notice the signal strength only in certain areas. Not trying to be patronizing, but these are the questions I asked myself when i noticed the same thing.

As for the Infiniti Logo screen, I too have noticed it taking a long time, more so than before. But that is a little subjective. I can be impatient. I put that down to the DVD spinning up and the Nav computer initializing.

I guess as long as you're receiving signal for 2D coordination, your GPS will work fine, however it is troubling.

Sorry I could not be more help.

Mike.

2003 6MT Coupe Black/Graphite/Prem./Nav/Aero
1994 MR2 Turbo 5MT Black/Prem.<P ID="edit"><FONT class="small"><EM>Edited by mchristsen on 07/24/03 07:45 AM.</EM></FONT></P>

 

On a somewhat related note, I've come to the conclusion that the nav system doesn't seem to update position with the GPS all that often, at least not always. Reason I say this is because everyday when I leave work, the procoess of circling down out of the parking garage (from 5th level) down onto the street seems to totally throw the nav system out of whack. Now I can understand that, after all it's probably not even getting a signal. But what really bothers me is that once I'm on the street and driving, the nav will _still_ be messed up, showing me driving on a different road and direction than I'm actually on. And it seems to take a couple miles, ie several minutes, before it will resync with GPS and show my correct position and heading.

I find this pretty inexcusable in a $2000 Nav system when my Timex Speed + Distance GPS watch ($140) can track my movement using up to 12 satellites with a much higher degree of accuracy.

Jeff Kohn
H-Town, TX
2003.5 Automatic Sedan, Desert Platinum/Willow, Premium, Nav, Tint

 

Dont forget that the NAV doesn't rely only on sat signals to get your position. It also uses the speed of the car and the steering wheel to determine your location. I read about it in the manual then proved it by doing a half a doughnut. After you do that and pull onto the street the nav is out of wack till you drive about a 1/4 mile.

 

If you're in a parking lot and spiralling down 5 floors, you're most likely not getting a signal. The Nav will either get your initial position from a weak signal or its last known position. From then on, it will rely on wheel position and speed to figure out where you're going, then place you on the most likely street.
If you start the car and begin to drive before it's received its signal, or before it's fully booted up, you'll throw it out of whack. It will say 'this was my last known position and direction' and you're already 50 feet away at a 90 degree angle to where you left it. If there's not strong signal, that'll mess you up.
As for the satellites, I noticed the day I got it that it flipped through 2-3D coordinates, however it's been pretty darn accurate, regardless. It only takes me about 50 yards for it to get back its bearings if it's off, too...
Finally, I've driven the Merc., Jag, Acura, and Lexus nav systems, and none of them are more accurate... in fact, I'd venture a guess that Lexus was the least so. Audi's is just pathetic.
G

2003.5 Black w/ Willow
Premium / Sport / Aero / Winter / Navi / Tint
Indianapolis, IN

 

jkohn, It sounds to me like you would like a full IMU based Inertial Navigation System (INS) in your car for only $2000. Good luck, these cost a ton more money for that kinda of Kalman filtering based DGPS coupled with an IMU (used in aerospace applications).

My guess would be if yo took your Timex through the same route, it would not tell you where you were at all. The amount of information that watch gives you is probably far less than the Infiniti GPS as well.

Let me tell you as someone who's job it is to design, test, and use navigation and telemetry equipment for NASA and various aerospace companies, the Infinit GPS system is very impressive in its seamless integration into the car. The software is very good. In mission critical situations (which Sunday driving is not considered) you would have to pay 100 times more for the kinda of accuracy and precision that some people want. What we have with Selective Availability (SA) off is very impressive. I did not hesitate to drop $2k when I saw the demo of the nav at work. I am a sucker for these things and this is a fine unit.

Danation.com - G35C CB/GR/NAV/PREM

 

I paid particular attention to mine on the commute to and from work today. I observed that it varies between Full Green and Yellow, but rarely goes White unless I'm in a tunnel or heavy overpass, or something like that. I did notice that it will fluctuate from Green to Yellow even while just sitting still at a stop light, interestingly enough.

I'm not concerned, though. The system should be designed to still track your course through "dead reckoning" (which is the term I believe others above have basically been looking for) based on your movements alone, even when it cannot maintain a satellite lock.

I took a road trip from Philly to DC last weekend, and it still placed me right on the doorstep of my destination, with no detectable margin of error.

To me, it seems highly accurate. No worries.

<font color=blue>2003 G35 Coupe 6MT - diamond graphite / graphite leather - premium - nav</font color=blue>

 

<blockquote><font class="small">In reply to:</font><hr>

jkohn, It sounds to me like you would like a full IMU based Inertial Navigation System (INS) in your car for only $2000. Good luck, these cost a ton more money for that kinda of Kalman filtering based DGPS coupled with an IMU (used in aerospace applications).

<hr></blockquote>No, I just want it to update position with the GPS more often, rather than relying on speed/heading. I understand that the system won't be getting a signal when I'm driving out of the parking garage. What I don't understand is why it takes several miles of driving before it syncs up and makes the adjustment to show my proper position/heading. What seems to happen is that the NAV system thinks I'm heading north on one road when I'm actually heading northwest on another road. The NAV system won't realize there's a problem until the road it thinks I'm on has ended and it realizes that since I'm probably not driving off the road it must need to resync with the GPS satellites.

<blockquote><font class="small">In reply to:</font><hr>

My guess would be if yo took your Timex through the same route, it would not tell you where you were at all. The amount of information that watch gives you is probably far less than the Infiniti GPS as well.

<hr></blockquote>Yes, it's a much simpler device. But it has no problem locking on to the satellites, and it updates the GPS information every second, providing very good accuracy for the information it does provide. The NAV system appears to update the GPS info much less frequently, and that is my complaint.

<blockquote><font class="small">In reply to:</font><hr>

Let me tell you as someone who's job it is to design, test, and use navigation and telemetry equipment for NASA and various aerospace companies, the Infinit GPS system is very impressive in its seamless integration into the car. The software is very good.

<hr></blockquote>I agree the software is very good, it's saved me a lot of grief several times. I just wish it did a better job of locking onto the satellites and checked the GPS info more often.

Jeff Kohn
H-Town, TX
2003.5 Automatic Sedan, Desert Platinum/Willow, Premium, Nav, Tint

 

First of all, GPS only updates at 1 Hz. That is the nature of the signals. My observation of the system leads me to believe that the software is making a best guess as to your location. If it gets it wrong, or it is waiting for a corrective measurement from the GPS to adjust the dead reckoning values, it will most likely assume that you are on a road (although I have some really screwy things) and that your heading is that of the road (although I have seen myself driving down a westbound road while the arrow pointed about 30° off the road heading). There are a lot of corrective and interpolativev tricks usually built into the software. If indeed the GPS updated its state matrices with "bad" information from the satellites (due to errors) the arrow would jump sporratically. You point is well taken though that in the interest of making the arrow appear to be smooth and on raods, you are losing some fidelty and accuracy of the overall navigation. This is a not a trivial issue that all navigation manufacturers/software people have to deal with.

Sailboats use full INS to get around coupled with dGPS. I am waiting for something similar for auto applications. That is when you will see the same accuracy that pilots see in aricraft...

Danation.com - G35C CB/GR/NAV/PREM

 

Geez35, I haven't noticed any problems at all so far with my unit, after reading your post, I have watched my link indicator and it is 95% green, only occasional cut to Yellow and I have not noiced any white at all.....Also has accurately tracked vehicle position since the day I got the car.......I just want the Russian Spokesmodel voice, Natasha, to sexily tell me where I am!!!!!

G35 Coup/Black on Black/Premium/NAV/Aero/Performance