Lightstorm

Hey all,
Just picked up my NBP/AT/Navi yesterday...very happy.

Has anyone noticed whether their navi lags behind? It doesn't matter if I'm going 35 ror 70, it seems the navi is behind about 50 feet, which in city driving could cause you to miss a turn.

Any thoughts?

Thanks!

rets

Marc, first of all, Congratulations.




My Navi is a little behind, too. But most of time I have no problems to follow its direction... Have you checked our Navi sub-forum yet?

Hope someone will come up and show you the ansnwer very soon.



Your thread will be moved over to Navi sub-forum later...

roadman

Your NAVI is behind 50 ft when you are going 70mph, what is that like 1 second behind ?

Lightstorm

Hey Roadman,
I don't think it makes a difference how fast I'm going. It seems to lag behind the same distance no matter how fast I drive. Have you seen the same thing?

Jss1

I think it just needs to be recalibrated. Mine tells me to turn about 50 feet before the actual turn.

JoganJani

MIne is very accurate. Exact turns. I think within 10 feet.

rvmeush

I have been having the same problem with the Navi lagging my actual location. It didn't seem to do this when I first got the car. I did some calibration to get my location accurate while stopped, but there is still a lag. If anyone has any hints please post them.

twong11219

The delay is caused by the Navi loosing connection with the GPS satellites. I get this all the time when I'm in lower Manhattan with the tall buildings surrounding me or when I'm starting my car in the garage. It'll automatically recalibrates itself in a couple minutes. Also, I think the delay is sometimes caused by me driving away before I hit the "OK" button. There was one time my Navi told me I was in the Hudson River and it poppd back to normal after a couple minutes. I wish there was a button to manually recalibrate if I knew it was wrong.

smiranda69

I have navi but don't really use it that often, but over the weekend, i did have the opportunity to use it and i noticed the lag as well. i just figured that that's technology for you...it's not 100% fool proof, but it does get you to where you want to go. i'm sure as the technology is more mainstream, there will be more improvements. overall, still very happy with this option and will certainly look to have this option in my future automobile purchases.

dannodaman

I've been using the NAVI a lot in areas with one-way streets, lots of turns, etc. and the NAVI seems to be pretty accurate. Haven't missed the turns (yet) ... It tells you to take "first" or "second" right/left turns, which I think is really helpful.

Sherlock

I love the navi, but it has some serious issues in downtown and midtown atlanta. Told me to turn on a street that wasn't there. Told me to turn on a street that ended up being the onramp to GA400. Tells me to turn left on Ralph McGill to get to my work which is a right-turn. knows nothing about the Newnan area.

I love it when it works, but it gives false readings enough that I hesitate following it now sometimes.

I did have to calibrate it once.. I stopped at an intersection and it showed me about 10 carlengths behind where I really was..

youngTL

It's not entirely the NAVI's fault. It's the nature of GPS...

dcarlinf1

Hehe, here's to a non-navi TL, a map and $2000 left over for CAI, etc.



Flame away, if you must

roadman

I have NAVI in my '04 MDX and it starts warning me to turn at many different intervals 1/4 mile, 500ft, 300ft, 100ft or 50ft. It seems pretty exact in relationship to where the turn is.

Data must be transmitted so there has to be a delay in reception, that faster you travel the more you have moved from your identified spot so the returned info will be off more. For example when I go over the GW bridge it shows that I am on a bridge, when I am moving slower (which is like every rush hour) I am in almost the exact location. When I go over at 55mph it of off a bit

TL A-Spec Owner

I have also noticed the same problem. I sat and played with the zoom feature and it seemed to be accurate at the 3rd setting, but anything in closer was lagging behind as others have expressed. I am wondering too if this is just a GPS technology isssue or whether it is something that can be corrected by the user. Anyone with thoughts or ideas?

TonySCV

Civilian GPS has often been operating with "selective availability" (SA). It's entirely possible because of the conflict in Iraq (or any other number of reasons) that SA has been turned back on. If it's on, then you will experience up to 100 meter (approximately 300 feet) random errors that SA adds to keep GPS a more powerful tool for the military. If SA is off, GPS units are accurate to within 20 meters (approximately 60 feet); although in good conditions, units should display an error of less than 10 meters.

In other words, your GPS response and accuracy WILL vary.

twong11219

I think the Navi also does one thing that is unrelated to the GPS tracker. If the GPS is not green on the display under the compass, it means that it can't detect a satellite signal. In this case, the Navi system switches to the car's current speed and "guesstimates" your position.

Also, there are certain things that the navi is not perfect on like the types of streets and certain directions as Sherlock mentioned. That's why there's a disclaimer everytime we start the car mentioning the system's not perfect and that we have to hit "OK" to continue. Just like Mapquest and Rand McNally. Nothing beats the brain of a local driver that knows his shortcuts and turns. But luckily that's only the DVD in the trunk and not the system. The newly released DVD should solve that problem. I would definitely send an email to Acura to make sure they update your area in the new DVD so when you do update it, the streets will be there.

jastor3759

I've used Garmin, Magellan, and a Pharos CF card with my iPaq as well as my TL and they all have some lag. But in comparison, the TL beats them hands down.

¿GotJazz?

I can tell you with little doubt that it's mostly a software issue.

I have tried 4 different Navi software packages on my PDA, and each one showed a different display accuracy. Since the hardware was identical (Holux 270 GPS module and Dell Axim X5) on all of the trials, it reduces the problem down to software. Destinator lagged about the same amount that the TL does. The best was TomTom USA, which was dead-on.

Since all Navi software will do some form of "stickiness" to the road that you're on, the Navi software tends to predict your travel path. Since the Navi system knows your current speed and acceleration (derived from the GSP data and a little calculus), it should be able to predict where to put your car on the display based upon the road that you're current driving on. This ain't easy though. It requires a deterministic software design that guarantees that the Navi display will always update a specific amount in an exact period of time. While this can be done, it's not the easiest way to design the software.

One side effect of implementing this is that there can be some "misses" on your location when you leave a highway, but those already seem to exist already anyways.

Given all this, there should be no reasonable excuse why the 04TL's Navi system doesn't put you at the right spot in an intersection when you have stopped for a few seconds. Yes, the GPS satellite system gives approximately 30 ft. of error, but that doesn't mean that it will be 30 ft of error all the time! This error amount is a random value.

Regarding the "selective availability" issue, I believe that this was turned off by President Clinton in the early 90's. And, I was eagerly watching my GPS receiver accuracy at the very beginning of the Iraq war - no accuracy difference was seen. Someone told me that the SA may be adjustable by the military to make it less accurate over specific areas of the globe during wartime without affecting the rest of the globe. I doubt this (The GPS system is pretty old technology), but I really don't know for sure ...

Sonic

My Navi works fine too

Nittany Lion

Nicely done!

EZ

Agent47

You have mettalic tint? Perhaps it is weakening your GPS reception.

pedalermike

It seems to be a map matching problem on the main nav screen - the accuracy is fine since when you get to a manover, the right hand split screen display is right on target with the number of feet. Looks like Alpine needs to tweak the display s/w...

Rocketsfan

No flames... but here's to a navi TL, no need for maps, and money still left over for CAI, etc.

Don't hate...

wv5b

That will definetely throw off your navi. If your car has not been tinted then maybe your system can be calibrated. I had a friend who tinted his tl and it messed up the navi real bad. It's like trying to listen to am radio inside a metal barn. my son and I have owned 4 tl with navi and not a problem.

CPanther95

My biggest problem with my Navi ('03 MDX) is the time estimates. My Dad's TL is too new to make a comparison, but my MDX is substantially worse than the '00 Odyssey navi I had.

If I made a 8.5 hour trip in the Honda, it might show 10.5 hours to destination, but once I got up to 70 on the highway, it would partially extrapolate my speed and refigure the time much closer to actual. Halfway through the trip (4.25 hours actual time left) the navi would show 4.7 hours left.

On the MDX, the same trip shows 11.5 hours. Halfway through the trip (4.25 hours left actual time) the navi shows about 5.75 hours left. It's as if it doesn't factor in actual driving speed for the remainder of the trip.

yober

I have purchased crushed 2000TL for parts and it came with the Navigation system.
I am wondering if it is worth it to put on my 2001TL?
Is this a good gadget? Does it work properly?
Please any ideas/advise would be appreciated

yober

Also , does anyone knows where the Climate Control disappears when you have Navi in that place instead?

Mr. Protocol

GPS accuracy will vary, but not due to SA. SA was turned off by presidential order
during the Clinton presidency and it will never be turned back on. The military now
has other options to deny access to GPS by enemies on the battlefield, using local-area
technology rather than screwing up the entire constellation. The cost of SA to
current civilian users is too high for SA ever to be turned back on.

If your GPS receiver shows all the info it gets from the satellites you can see this
in the "estimated error" that each satellite reports. When SA is on, it reads "32
meters". When SA is off ("set to 0") it reads more like 4 meters.

You can see this information in the TL. Press the three buttons Map, Menu and
Cancel at the same time and hold for five seconds. This will bring up the car's
diagnostic screen. DON'T MESS WITH THIS OR YOU'LL F*** UP YOUR CAR FOREVER.
Got it? Let me be clear: DON'T MESS WITH THIS OR YOU'LL F*** UP YOUR CAR
FOREVER.

That said, press "GPS Information" to see a sky map of the satellites you've
currently acquired. Fun, but not to the point. Now, press the Menu button
(alone) for five seconds to get to the detailed status page. This shows all
the info about all the satellites. No SA, see?

This page also shows HDOP and VDOP, too, by the way. Lower is better. This
gives you an idea of the goodness of your current navigation fix. 1.1 is fantastic,
1.5 is good, 2.0 is not so good, >3 is time to blank the screen and forget about
it.

CONTEST! CONTEST! CONTEST!
Who can expand ALL of the abbreviations of the column names on the detailed
status page?
CONTEST! CONTEST! CONTEST!

Thus endeth the lesson. Hope this helps.

Intox1221

Okay this might sound real dumb, but the antenna for Navi is inside cabin of the car ??? I thought it was embedded inside with the XM antenna in the middle bottom of the roof.
04' TL Desert Mist/ Parchement
Navi

Mr. Protocol

Yes, it's located beneath the covering of the rear window well. Or so I
hear. That's why you'd better not use a metallic tint on the rear window.
The patch antenna on the roof is apparently purely for XM.

DC5_Integra

My Navi does lag behind slightly during my normal driving .. But when the navi is telling us where to go, the voice thing and when it zooms in for a turn ahead is quite accurate

pedalermike

Well, I'm getting pretty irritated by the navi lag - sometimes its ahead and sometimes behind. I figure on most days its at least 100 to 200 feet off. The strange part is the manoever screen (the little window on the right) seems to be spot on so its only the bird's eye view (on the left) that is off. I called ACS this morning and they claim that the car is operating as designed and that it is normal for it to have a large variation to where you are. The Regional Manager seemed to ignore the point that the manoever screen is right on and that only the birds eye screen is off. I get much better accuracy with my el cheapo Garmin eTrex (+/- 10 feet) than I do with the Alpine system. She offered to compared my results with another TL and that if they match, everyone is ok. I told her that is like comparing my limp to the guy next door and that if we both limp, then that is ok. She referred me to page 69 of the manual...

What a load of BS, ACS needs to train their folks better - anyone schooled in the art of GPS will know about how to get accurate fixes and using map matching algorithms to fill in for anolomies.

Is anyone else frustrated by this? Oh, my software is v1.0400 with DB 20030902. Is anyone with v1.0410 having this issue?

Zeuser

Mine is very very accurate.

Your system may need some recalibration, which you can do yourself if you know how.

You also have to understand a few things about the TL's navi. It's not just GPS. Sure it uses GPS to get your position but it also uses a YAW sensor and the vehicle's speed sensor. All 3 systems are combined to give you the most accurate position and speed as possible. But as in any scientific instrument, there's always an error margin. And the larger the error margin in one subsystem, the larger the error margin overall.

Things that can affect the error margins:

GPS:

- Cloudy days (loss of signal or signal refraction)
- City driving (signals bouncing off metal structures)
- Hot and cold (varies the timing of signals)
etc.

Yaw sensor:

- Rapid direction changes (like going fast around a hairpin)
- Rapid Acceleration and deceleration in a turn
etc.

Speed sensor:

- Worn tires
- Aftermarket tires
- Wet/snowy road conditions

Although the TL's speed sensor is set for automatic calibration, I still suspect that the usual culprits that affect the speedos on every other car also affect the TL's navi in some way.

JetJock

My navi works great...it's spooky how accurate it can be. It shows exactly the position of the car in relation to the road I'm on. Even on a divided hwy, it shows which lane I'm driving in....that's spooky!

NFLblitze1

The Navi is amazing.....even though the navi says my house is .4 miles up the street......it dosn't bother me that much...