Ah. You want to update the actual maps in the navigation unit. Youd have to source a new microSD card that is UNLINKED. But you need to check with a dealer for compatibility, A lot has changed in 10 years as far as infotainment.

I was referring to the topic of the thread which is the GPS recall sending inaccurate location data for enform and other emergency services.

 

Here's what I recall about NAV data.
I've had some experience with several Lexus NAV systems since getting my SC430; I don't recall the GEN numbers, but you can look those up easily.
The SC430 came out in 2000, and was one of the first to use a DVD to store the map and POI data on it. Previous NAV systems used CDs, but the CD held much less data; I recall that the full set for the USA required about 8 CDs, and you would have to swap them in and out as you moved about the country. The DVD solved that problem by having all of the USA (and Canada) on one disc.
My 2004 RX had the same system, and I could swap those DVDs between the cars. The DVD method was used for quite a few years.
The problem with the DVD, besides the reliability of the drive itself, was the high cost of making a DVD every year; the discs were expensive. Eventually, car makers moved to having a hard disc in the car which would hold the map data. For an update, the dealer would have the current data, and would copy it to the car's disc drive.
At this point, the dealer became necessary because nobody else had the current data, which was impossible to get off of the car's drive (of course!).
Tech savy readers would think that the next step would be downloading the data from the vendor directly to the car, but there are two problems with that: to do it all at once took too long, and to do it piece by piece (like a phone app) required the car to be "connected," which it not always is. As far as I can tell, the next step was to replace the hard drive with small SD cards to hold the data. That's what I have in my RC, and I don't think that has been changed yet.
The Micro Card is about the size of a thumbnail, and goes into a slot behind a little door in front of the gear shift lever. It's much less expensive to make and duplicate, so it costs much less than a DVD, and does not require a dealer to install, and the system has no moving parts, so it's much more reliable, as electronics go.
Knowing what kind of medium your NAV data is stored on answers many, many questions that keep popping up here about how and when to update the data.
I think this everything here is pretty accurate, but you can read the following posts to see corrections and additions, if any.
That's about all I know on the subject.
Thanks for asking.

 

Do I have to have been signed up to Lexus Enform or can I just bring my RC in?

 

FILLAY asks: "Do I have to have been signed up to Lexus Enform. . ."
I think that's not too important. If the service guy says anything, just sign up for Enform for a month, and then cancel.
You should be signed up anyway, you tightwad!