I don't know about the newer models with nav, but my '04 will only do door-to-door routing in large metropolitan areas. For example, when I leave my house (I live in a small town) with a destination programmed, the nav will only start the instructions from the nearest major road. It shows the starting location on the map and tells me I have to figure out how to get there myself. It won't take me from my driveway like my Magellan does. So I'd like to know if this would be improved if I get an update.

 

I second that question. I still can't get over the fact that they put an outgoing generation Nav system in a newly redesigned model (04 RX330).

Also I assume if I buy a 2010 NAV update for my IS (Gen 5), it won't do any good if I put a copy in my wife's 04 RX330 (Gen 3).

 

I don't think it's worth mixing generation dvds. I'm pretty confident the gen 5 disc won't work in a gen 3 system. Best case it just wont read the disc. Worst case it will try to update the firmware but ultimately won't be able to and it won't load the gen 3 after that. I certainly don't know that would happen but these systems are touchy enough I do not have the nerve to try it.

As for a new dvd (correct generation) for your car. I would think jump from 2004 to 2010 would get you a lot of newer roads and points of interest. But I don't think there is any way to know for sure if your town has been mapped. Depends on how small of a town and how far from a major road it is I guess. I thought there was a site you could go to and enter your address and see if it was mapped for the Lexus systems but I can't find it. In my experience the factory installed navis aren't ever going to be as good as some of the best after market devices that are available no matter what dvd you use. That said, I don't drive any obscure routes so have found my factory installed system adequate.

Good luck with whatever you try.

 

Just returned from a 3-day shakedown road trip in our 04 and found a few major roads that were either not accurate or just not included. A couple have probably been completed since the GPS data was collected eight or so years ago and I would think they would be included in an update. However, coverage of old roads in even the smallest towns was pretty good. And we went through some very small hillbilly towns in West Virginia. So to clarify my question, it isn't necessarily the lack of roads it is the inability to route to an address in areas outside of large metropolitan areas. The roads are in there but the address systems for those roads must not be.

 

You can go to http://www.navteq.com/ to look at the current maps. In general, if an address or a poi is there, it's likely also on the newly released version 10.1 maps.

And no, you can't use a different generation disk than the one for your vehicle. Here's a useful site for which cars use which generation: http://www.toyotanavi.hu/navigen_.html

At least toyota is updating. I've got a 2004 Cadillac XLR, and GM isn't releasing any new disks for it after 2009. It's got a Denso gen3 nav system, so Toyota gen3 nav disks work in it, as long as you don't mind no audio guidance.