kitlz

JB, the auto high beams have worked pretty good for me. But I keep it off though with all the traffic. Defeats the purpose just like laser cruise control

BertL

...sort of off-topic from the primary purpose of this thread, but I had laser cruise control on my previous BMW 335i, and found it very scary when it would speed-up on some of the 2 or 3-level 90-degree+ overpasses we have here in SoCal when nothing but air was in front of it on the curves. I was skiddish to use it after a couple of those unexpected experiences except on long open terrain, and didn't order the Lexus version on my new 450h that should be built any day now for that reason. I had to order the LED headlights to get the "luxury package" even though I saw little value in the $1800 option, and suspect I'll not make any big use of the auto high beam option, as it too, probably is not very foolproof in practical use except on the occasional road trip through wide open spaces.

kudzurunne

Somehow the "r" got cut off the end of my handle. It should be kudzurunner.

I actually joined Club Lexus forums because of what I'll call the "lousy nav system" issue, one that I discovered for myself yesterday and then was delighted (or depressed) to discover is a significant issue among Lex owners.

My 2013 RX 350 is one week old and I love the heck out of it. But the nav system, with factory settings, is obviously non-optimal. Yesterday it told me that the 55 mile trip from Tupelo to Oxford, MS would take 1:36, when anybody knows that it only takes an hour. (Google maps has 60 minutes; my Garmin nuvi has 57 minutes.)

I've used the Garmin for the past three years with great success when I go off on long-weekend or two week roadtrips. I'm a part-time musician and having accurate distances and ETA's is absolutely critical to making a tour function smoothly. So this is a huge issue, and it freaked me out.

A little research made clear two things:

1) I needed to adjust the three speed settings in the setup preferences

2) Lexus, which is ahead of the curve in every other way, seriously lags behind Garmin and others in the matter of navigation technology--at least when accurate ETA's are concerned. Garmin, as I understand it, knows the speed limit on every piece of road on your planned route, so the ETA is calculated from that. (As a result, it also lets you know, in real time, when you're exceeding the posted speed limit--a really useful thing when limits suddenly change and cops are waiting just across that pesky Iowa state line.) Lexus doesn't.

I was gratified to discover the handful of threads devoted to this issue. But I was also determined to see whether I could optimize my Lexnav in a way that would give me basic confidence in its ability to shepherd me through a tour.

What I did was come up with a list of 11 destinations, from 55 to 1150 miles away. These are places I've actually driven to. First I mapped them with Google maps to get distance and ETA (or, more precisely, TTD--time to destination) data. I did the same thing with my Garmin. This gave me a reasonable baseline: a pretty accurate register of the true distance and TTD.

Then I ran those destinations through the Lexnav five times, beginning with the OEM mph settings (25, 35, 65) for in-town, regional, and highway speeds respectively. The other four settings were:

1) 25, 45, 70
2) 25, 50, 65
3) 25, 50, 70
4) 25, 55, 70

The results were fascinating--and heartening.

First, at least when mapping trips that begin where I live (Oxford, MS), the OEM settings lead to atrociously inaccurate results. This has something to do with Interstate speed limits around here (and in Tennessee) being 70, but that single fact doesn't explain all of the problem. The 35 mph middle setting is also way too low.

Second, although no single set of settings is perfect, the last two (25, 50, 70 and 25, 55, 70) are surprisingly accurate. On an 1150 mile trip to suburban New York, the 25/50/70 setting gets me there within 5 minutes of the Google/Garmin estimate--in a trip lasting more than 17 hours!

Thirdly, a musician pounding down the highway towards the next gig would always prefer to be slightly ahead of time rather than slightly late, which means if I have a choice, I'd always prefer a nav system that tells me that my TTD is slightly longer than it actually is. That being the case, setting #3 (25, 50, 70) works best for me--which is to say, it comes closest to equalling the average of Google maps and a Garmin. This is especially true at longer distances. At shorter distances (under 100 miles), the top setting (25, 55, 70) seems to be slightly more accurate. (These results surely have something to do with the direction I'm traveling on the longest trip, which is East. Highway speed limits fall from 70 to 65, for the most part, as you head east and as I-40 gives way to I-81 (except in W. Va.)

Fourth, the Lexnav generally came up with a trip distance that was very, or reasonably, close to the distance given by Google/Garmin, but on several occasions there were significant anomalies. The trip from Oxford MS to Mankato MN was almost 70 miles and an hour longer in Lexnav than in Google/Garmin. So no matter how well one optimizes the Lex, it's probably a good idea, at least with long trips where the ETA is crucial, to use Google maps as a backup.

I have put all the results into an Excel spreadsheet and uploaded it to Tradebit, a filehosting site that I've used for six years. If you'd like to download it for free, you can do so by accessing the following link:

http://www.tradebit.com/filedetail.p...av-faceoff-xls

There's a lot more to be done here, but the basic principle seems sound to me. When confronted with a non-optimal system--which the Lexnav plainly is, as any Garmin owner will attest--don't assume the worst. Engage in retail optimization. Plug in a lot of data, adjust what is capable of being adjusted, and optimize the non-optimal system in an incremental way. Then reassess.

If you don't have a Garmin and don't want to spend a couple of hundred bucks just to optimize your Lexnav, then just use Google maps. It'll give you a pretty good baseline. Choose at least 5-7 different destinations--different directions, different types of roads, different trip-lengths--and come up with distance and TTD data. Then run those same trips through your Lexnav, tweaking the three speed settings until most of the trips hew fairly close to the Google results.

What this experiment has shown me is that I'm likely to bring my Garmin along on working roadtrips and start the morning by running BOTH the Garmin and the Lexnav, just to see whether they're in reasonable agreement. If they are, I'll turn off and stow the Garmin. If they're not, I'll try to figure out why they're not; I may tweak the Lexnav speed settings and see if that helps.

Cheers, everybody! I love the heck out of my new car--my first new car, at age 54, after a lifetime of used Hondas. Big step up!

coachlkg

Pretty annoying when my "cheap" Garmin is more accurate than my Lexus Nav.

coachlkg

kudzurunne, you have provided some great information for optimizing the Lexus Nav destination accuracy.

I used to compare AAA online triptik with my Garmin. They were usually the same. I will now compare AAA to Lexus NAV.

MacCat

I love my TomTom (1505) series.

My favorite feature is the vehicle speed.
It's digital and turns red when I'm over the posted speed limit.

My problem is that TomTom has ignored my please and emails to update it's database. I has not recognized new and mostly higher speed limits in Arkansas and Texas. Oddly, that hasn't affected it's ability to accurately post my Estimated Time of Arrival (ETA).

I am annoyed at how awkward it is to attach to my dashboard or windshield, and that's a major drawback, because it's hard to see if it's way forward in the car dash. I actually attached it to my drivers window at one point..

Also, it's pretty tough. it's fallen off the windshield many times and so far, hasn't been damaged.

The USB cable, however, is an awkward and very tight fit.

My Lexus Nav system (2010 model) has been pretty good with ETA and distance in Texas, even with the new speed limits. Now, if it just knew more about long term road projects and detours. It tells me nothing about nearly 100 miles of active construction work from Austin to Dallas, which has lower speed limits and very heavy congestion at times. It's not uncommon to see miles of traffic backups on the week-ends.

So, I still use the TomTom in my other car, but not the Lexus.

DunWkg

Gotta agree with ya Mac, drove down to San Antonio through that nightmare called Dallas. Don't know about weekends, but the weekday my speedometer was of no use. The needle does not move off of the peg a lot of the time.

Will skirt around that miserable section of the Texas highway system on the way back home. Rumors of a toll road called Highway 130 brings hope to my heart. Will download some waypoints to navigation tonight for the trip tomorrow. Just wish my "E-Z Pass" worked in Texas toll booths.

KeithPI

I found the same problem on a recent road trip in my new 2015 RX. The default settings had a day long drive more than 3 hours longer than it should have been. I did find that it seemed to adjust and catch up during the course of the day. I will try some of the tweaks suggested by Kudzrunner to see if we can dial in the accuracy a little.

jfelbab

I must be the only guy here that actually likes the Lexus NAV system. It just fits with the way I work.

I've had NAV in my Lexus vehicles for over 10 years. I've initially set the NAV to 25/50/70 and get pretty accurate initial time estimates. The NAV does adjust the time remaining as you travel the route based on your progress.

Outside of the "mouse" interface, I don't have any problem with the Lexus NAV system. I especially like the traffic redirect capability based on SIRIUS real-time traffic data. This has saved me from huge delays numerous times. I find it convenient to be able to change my chosen route or destination via my MacBookPro, iPad or iPhone from my home or hotel room with eDestination and push it to the NAV or use Lexus Destination Assist and have them push it to my NAV.

All-in-all, it is not a bad system, IMO.

kitlz

No Jim, you're not alone. I like the nav system too. Only complaint, it didn't reroute me a few weeks ago with a destination entered. Wound up sitting in an hour of traffic I've had nav in the RX for over 10 years too. It's much improved over the 2nd gen. I think you'll agree that's true with many other features on the RX. Some of us maybe appreciate it more. Lexus does get around to updating things, albeit a little slower than most people like.

Cruiter

Anita, Jim & others
I don't think there's a NAV system running that 100 % of users would say is perfect. There are just too many out there with different features that some like and some don't care about. That said I can see improvements for Lexus or any other that would be nice so let me give an example of something I do like about it I can't get on the GM NAV and really miss. I LOVE the cookie crumbs to back track you out of what ever neighborhood with umpteen turns you went into. I leave it on constantly, doesn't bother me as it does for some. I think all 'nice' cars should have NAV, they should have cookie crumbs, and they should have a Heads Up Display. Chips are cheap today and it just involves the flash to program them. While I like the NAV in my Lexus better than my new C7 Corvette Stingray, I LOVE the HUD in the Vette. It blows away anything I've seen anywhere. I squeezed that in because the NAV works with it and trying to stay on topic . But it doesn't have the Cookie Crumbs and that just fries my brain

elba123

Perhaps this depends on the location you live in. Many a time, I have overridden the suggested deviation and found no blocks in the traffic. There are times I have listened to it and regretted it. SF bay area traffic is always bad during week days. So perhaps that's why. I let Sirius complimentary subscription lapse as this traffic redirect feature did not work and could also never figure out how to use the weather feature.