Sat Nav Accuracy

I too would suggest trying the routing with motorways off or on; see if there's a difference. It's possible one of the smaller roads is mismarked internally as a motorway.

Also, be sure there are no "areas to avoid" registered in the nav. These areas will always be avoided in routing, even if you were to request a detour while enorute.

And you're sure you're not choosing "quick" versus "short"...

 

I'm experiencing the same problem with my shiny new prius, what I picked up on Saturday: specifically, it sticks to major roads and avoids thin black lines.
It's amazing; it wants me to

• make right turns (in .NZ, that means crossing traffic, think Left Turn for you Americans / Europeans / other 96% of countries) on traffic lights with no right-turn arrow (typically I avoid this: oncoming traffic can be painful on paint and person)
• drive past a perfectly good turn, out to a busy road, and then double-back across busy traffic to get to the same place I can achieve by turning right, right now (i.e. drive 3/4 of the way around the block)
• drive a complete circle around my house to get to the one road it considers worth driving on

Clearly delusional; even if she does have a nice British accent.

It's possible the option to set time estimates has something to do with this...
I found a setting to estimate voyage times; it was set to

• residential - 40 kmph
• main streets - 55 kmph
• freeway - 95 kmph

Thus, if it thinks thin black lines are Residential, it's going to go around them because it will think main streets are faster (although longer), even when they are not!

I can't make residential any faster, despite the fact .NZ has almost nothing signposted below 50 (roadworks, carparks, schools ...); we tend to go 50/80/100 or 50/60/100 for street / "arterial route" / open road.


I, too, would love a menu setting that enables me to 'improve' this behaviour, at least around towns I know. It's a good thing I know the best way to get to work; because my car certainly doesn't!

 

I experience the same mystical routing that is described here and I agree that it can seem a little baffling at times.

In a nutshell, the Toyota NAV is programmed to not guide you through "residential" areas but rather stick to main streets, even when using the "Short" route setting. It can be frustrating for sure, when you know the neighbourhood and that there is a shorter way, but I am also sure the reason it was developed this way is to keep traffic where it should be.

Speaking as devil's advocate, if you lived on one of these small streets that conveniently acts as a shortcut for others, would you appreciate people's NAV systems creating unnecessary traffic in front of your house all the time? :huh:

Anyway, the solution is simple - if you know the area, just ignore the guidance and drive the way you want, it will recalculate with each (missed) turn. If you don't know the area as well, try using the "Dual Map" view to get a higher-level view with your left map at 200m (600ft?) zoom and try your own shortcut. Within a couple of turns, it should jump onto track for most cases.

Of course, these issues are very regional, so YMMV.

Lastly, as someone else pointed out, these travel speeds in the preferences has no impact whatsoever on route calculation, only on arrival time.

 

Having driven a couple more times, it seems obvious that lil Emily definitely routes you off the thin-black-line streets.
Which is kinda sad when, as mine does, your town* consists mostly of thin black lines, with only a few occasional "main" streets; and the so-called main streets are usually where the worst traffic is, and thus are the best places to avoid!

So it would seem the consensus is that Emily, the magic speaking voice behind the dash, will get you where you want to get to. But if you already know which way to go, you'll probably do better on your own

* at 100-120,000 people, Hamilton is the 4th or 5th largest "city" in New Zealand. It doesn't even have mass transit / subway / light rail / elevated rail. It's not a city, it's a town!

 

<div class='quotetop'>QUOTE(Alex Brown @ Oct 20 2007, 10:49 AM) [snapback]528119[/snapback]</div>

I think you're onto something here.

Here in Norway, the Police is getting tired of foreign truck drivers getting stuck on small gravel roads in the middle of nowhere just because their GPS systems sent them on the shortest route. This will sometimes be a tiny private farm road barely negotiable for farming equipment, but as it is on the map, the GPS takes it into the calculation. So the Police is trying to tell people to use common sense, but that seems to be on back order for many drivers.


-Stein

 

I've heard that England has similar problems.. With "easy" road access to the rest of the continent, foreign truck drivers can go wandering around narrow country lanes with nothing but a Satellite Nav box for (mis)guidance. Local drivers, of course, know better.
So maybe there is something to this "main roads only" theory

Of course, I can do one better. Right near where I live is a pedestrian walkway, to allow people to walk out of this maze of little streets and onto the main road (no idea why, there's no shops by the walkway; must just be a general 'escape route'). The walkway has cast iron bars, painted white, to make it difficult for bicycles to use the "walk"way.
Emily, the talking lady in the Sat Nav box, keeps trying to get me to drive my prius down this narrow path! - This map proudly sponsored by Joe's Panel And Paint: See us First!

Can't blame Emily/Toyota too much though - Google maps makes the same mistake!

So, I guess the truths of satellite (mis)guided cars includes

• When the speaking voice tells you to turn, first check there is someplace for the car to go
• Locals can find better routes than the talking voice
• The box is not magic, you still have to think about where you are and what you're doing.

Take care!

 

<div class='quotetop'>QUOTE(Alex Brown @ Oct 14 2007, 11:09 AM) [snapback]525475[/snapback]</div>

How did you get to the Tech Menu in a 2007??

 

<div class='quotetop'>QUOTE(Inches @ Oct 26 2007, 05:29 AM) [snapback]530289[/snapback]</div>

I can't speak for Alan; and the American model may be different anyway.
On mine, I hit the "menu" button (physical thing, top right of the display), then hit the "display" button (top left). About a half inch of the top and bottom of the screen should now be covered by brightness and contrast controls.
Fairly quickly (don't hurry, but don't hesitate either) push

• the left hand side of the screen, just below the top adjustment bar that "display" bought up
• the left hand side of the screen, just above the bottom adjustment bar that "display" bought up
• top place again
• bottom place again
• top place again
• bottom place again

A "system check" screen should come up and take a few seconds to verify your Prius is happy, and you can now sneak around and look at the various technical bits.
When you're done looking, it can be hard to get out. Either power off the car, or I think pressing and holding the "display" button for about five seconds will restart the MFD.

caution
Be aware that a lot of people have found that certain things in here are very dangerous. In particular there appears to be a "load map" function in the Nav menus that completely trashes your Nav system
There are several other threads on here about this, a quick google for "prius secret menu" got 317,000 replies; many from PriusChat
Several of them have pictures; and it seems there are several different mechanisms - most involve the pushing on the screen up-down-up-down-up-down, but there's one with headlights on/off...

If it helps, I could throw up some pictures, as soon as I find my car (and my camera)...