EricSanDgo

My last two Honda vehicles had nav systems in them, and they never once experienced "drift" (where the indicator drifts off the road you are on and takes a while to get oriented).

My friend loaned me his TomTom to use in my rental car in early October. It experienced this "drift" issues.

Now I bought my new xB in late October and was suprised to see the menu system resemble the TomTom. The actual map screen doesn't, but the menuing does.

Additionally, my xB seems to drift fairly often too.

Do others have this problem, or should I take mine in and have the service department look at it?

It's not a huge deal, just odd in my mind, especially since I know Alpine made the nav unit for Honda, and I heard they also make the SNS (though am not positive). If so, it would be odd that one has this issue and the other doesn't.

Gotta say, I love this car though. I'm going to do the bypass on the SNS lockout soon, and I'm going to move my iPod jack to the glovebox if I can figure out how to do it.

I wish I had the time, money, and patience to put that sound deadening all throughout my car like someone else did, since it's a little noisy compared to my last car, but with the stereo cranked I can't tell! (LOL)

stick_1NZ

Have mine for 7 months now and never noticed a "drift" on the indicator. Moving your iPod jack inside the glove box would a good idea, there's a DIY for it around here.

rockthebeef

Hey Eric

My SNS does not drift either, That's odd.

...and I haven 't forgotten about you. Work has gotten from bad to worse overnight and I need to take care of a bunch of stuff by Monday.

EricSanDgo

No problem man, I'm in it up to my eyeballs too.

It's odd, the TomTom did it all the time.

I read the SNS manual and there is a WHOLE PAGE in the back giving all the various reasons why the car indicator may drift off the road. I was shocked when I found the page, since it seemed stupid to list stuff like "intersections that are not right angle corners, curvy roads, etc... All I can assume is that the system checks GPS position less often than it did on my Honda. Since you live close, I'll have to have you stop by my place some day and see what happens when you pull out of my parking lot on to Robinson going west. Mine drifts off and starts wandering south of Robinson almost every time I leave my house, and doesn't get "oriented" until I get to Centre St. It's weird.

rockthebeef

Yeah, we'll do that after the year-end crunch at work (after Dec 4th). Or maybe I'll drive that way and see if get the same thing.

EricSanDgo

No rush, I'm pretty buried through the holidays too.

HareBrained

A GPS system determines location by "acquiring" 4 or more satellites. As the sats are geo-stationary, the data is used to determine the relative position of the sensor to the sats, yielding lat, long and altitude (yes, it determines altitude, it just doesn't display it.) It's possible to determine location with 3 sats but it's accuracy is decreased (larger circle of uncertainty, normally 1m radius for 4 or more sats.) If you are acquiring only 3 sats, you might see what you're describing. This would be evident if you could see the instantaneous speed as it would assume you weren't moving and then going really fast as the vehicle passes thru the uncertainty circle for the previously determined location.

Back when there were separate military and civilian signals, this was very common. The sats used a built-in uncertainty circle of 10m for civilian operation. But if a person went to a known location, they could determine the sat introduced error. That's why there's only one signal now.

EricSanDgo

Thanks! I was actually aware of a fair amount of that information.

I just wondered if others encountered this, since I live in the same place I lived when I had my Honda and never had the "drift" issue. I was additionally confused because I had heard that both nav head units were built by the same company (Alpine).

rockthebeef

I'm actaully really confused as to how much Alpine is involved with the SNS. From what I've read I think they are only responsible for some of the audio processing funcionality - the CSE and digital sound processing stuff (which I've never been a fan of). I need to re-read what Scion says about this. I think they word it very carefully so as to subtly imply that Alpine did not make the entire head unit. The navigation portion of the system could possibly be made by a different company alltogether.

but I could be wrong... wouldn't be the first time.

Deves

So do I assume that there is no Speed sensor used on the Nav units to predict postion either?

On my Eclispe nav it used the Vss signal wire also but it was installed in a different car.

EricSanDgo

I have decided to take this into the shop and have them look at it, it happens CONSTANTLY, and I'm getting kind of tired of it. I am only assume that perhaps my antennae is not working properly.

Rock, I left 30th and ElCajon today, driving west bound, and turned south on Park. From 30th and EC to Park, my system wandered all over North Park, not locking to a street, and when I was about 3 blocks from Park, still on EC, driving westbound, it locked me on to Park going northbound. When I turned south on Park, it jumped me to Madison going west.

I'm sick of this crap.

rockthebeef

That sounds pretty bad Eric. Sorry to hear about the troubles. Maybe the GPS antenna fell out of place? Hopefully they'll fix it or just install a new unit. My SNS has been good. Even if I disable it to type into the screen, when I flip the switch back on the car will be back on track within seconds as long as I'm moving. We might have to potpone doing to mod to yours until this is all squared away... I feel your pain. I hate when stuff doesn't work the way it should - total inconvenience.

EricSanDgo

Yeah, it's gettin' totally annoying and worse.

I thought someone said you didn't have to flip the switch back and forth after the first time in the work-around thread. They said if you left it in one position or the other, when you shut off then start the car, it didn't have to be flipped any more. No?

No problem on the postponement, I agree, it needs to be fixed first.

rockthebeef

You're probably right. I noticed one day that I started the car with the switch off and the NAV was tracking just fine.I keep forgetting to test it out properly though. I vaguely remember that thread where this was mentioned.

GO CHARGERS!