My '05 nav system "falls behind" over a relatively short distance causing it to eventually skip to another road and go way off. I've updated the map but did not help. Has not always been this way. I tried resetting the new tire calibration but honestly have no idea if I did it properly. Any suggestions?

 

Is your car a 2005 SC430 or other 2005 Lexus model? If so, I'll move your thread to the appropriate sub-forum. This is the 1992-2000 SC300/400 sub-forum.

 

yes it is a 2005 SC430. Apologies!

 

After a rough couple months, back on track with this problem.... In Gen 4, should there be a "GPS" graphic in the upper left side under the direction/scale? If so, that is missing from my display. Might elevate this to obvious problem/solution? The system never 'resets' on it's own. Have to manually calibrate. I got into the service mode and the gps coordinates are not changing/updating. More likely antenna in dash or in trunk? Not sure I understand difference except dash extensive involvement to repair

 

Still lookin for a miracle answer to this question, I guess. Any other diagnostic suggestions? I'm afraid $800 just to take apart dash seems silly. Everything else works on unit, just no gps letters in upper right.

 

If I recall correctly, on the Menu options there is a calibration menu. Not the tire calibration menu, but and actual map calibration where you can adjust the center of the map. maybe that might fix your problem? For example park your car at corner of two cross streets. Use the calibration to put you as close to that corner as possible. Worth a try. Additionally, in my 2002, the GPS sign only comes on from time to time. When it's not on, the CD should keep a running track of your position until the GPS signal returns. That's my experience with the system. Maybe the area you live in doesn't have GPS coverage?

 

I have a gen 2/3 unit but it has a direction in the upper left with a scale for the map. Just below that square with that information is where the GPS symbol/letters will appear but that is the upper left, not the upper right. (I was going to take a picture of mine but it wasn't receiving in my garage. Maybe when I go driving around tomorrow, I'll remember to take a picture of it.

 

Do you have a factory radio, or have you swapped it out for an aftermarket?

This post is not much help, but it does show other people have your same problem and it does offer a couple of suggestions
http://us.lexusownersclub.com/forums...na-connection/

 

Thanks for the replies! My error on the gps letters. They should be left. I have repeatedly tried recalibration. And I did see the antenna link. I'm afraid it's one of those routes but wanted to see if any other suggestions. Dealership is not anxious to take dash apart and I know enough just to cause trouble. The radio is original. I had the recall airbag replaced several years ago as well as a new touch screen. I just hate to have the investment sit there worthless!

 

I have a 2005 I bought new. I have upgraded the navigation software when ever it was released. Now with the most recent available upgrade my navigation gets wonky from time to time. it does work but occasionally it gets lost temp 2 min maybe 3 and then gets back on track. I now use my phone makes better sense to me since the maps are always current. I would not invest in a repair like the costly antenna repair, Since you did have the air bag recall done perhaps your nav antenna is not plugged in all the way or is loose. I would check that before I would invest dashboard job

 

Can you get to antenna without going through dash? I was under impression it took that to get to it

 

The nav antenna does plug into the back of the navigation unit . You will have to remove some ac vent and trim pcs as well as the air cond control module and the radio not difficult at all. You then remove navigation and you can see if antenna is plugged in. If I am not mistaken the actual GPS antenna is way up against the firewall and does require the dash to be removed . You can first see if the GPS antenna is plugged in search forum or utube for removal of navigation

 

If it is that easy to access you could always buy a used antenna and see if that resolves your issue. http://www.ebay.com/itm/02-2010-LEXU...5WasVD&vxp=mtr

The OEM is pricey, but I wonder if you can get buy with a generic Lexus GPS antenna for $12 http://www.ebay.com/itm/New-Antenna-FOR-TOYOTA-LEXUS-MERCEDES-FORD-PANASONIC-ALPINE-KENWOOD-GT5-GPS-/330984329375?hash=item4d1034109f:g:yBUAAOxyJs5RcLs1

The harnesses look really similar

 

Anyone ever try/find a garmin type gps that simply fits in allowing cover to still close?