New to the forum and a noob at this at the same time I currently have a Garmin Nuvi 250W unit maps currently on it are City Navigator 2009 and 2009, I wish to put on 2011 although what or how do I need to remove to get rid of previous versions.
Any links to this process or personal assistance is appreciated and I thank you for your valuable time in assisting me in this matter.
Specs of my unit can be seen here.

Code: Select all

https://buy.garmin.com/shop/shop.do?pID=37416#specsTab

Hi There...

There are three maps on most Nuvi GPS. They are...

World / Base Map - GMAPBMAP.IMG
Pre Loaded Map - GMAPPROM.IMG
Supplementary Map - GMAPSUPP.IMG

I am assuming that you have either a gmapprom or gmapsupp file. If it's already unlocked, it's a simple matter to copy and paste the new map into the Garmin directory on the GPS. It will over write the other file so you may want to backup you Garmin directory first though.

If it's not unlocked, then you will need the GPS ID, MapID, and the keygen to generate a key file to match your GPS to the map you want to unlock. This is just a text file with the relevant UNL extension for the file name.

I am not sure if the 250W has a SD slot, if it does, then copy your new map to a Garmin directory on a SD card and the GPS will read that as well.

Regards to all

Col
Sydney Australia

Thank you for the reply colint I appreciate it greatly. I have the gmapsupp as well as a gmaptz if I am correct that is the time zone file is it necessary to change that as well?

Hi Again..

I have never used a timezone file before so I can't comment on what it's used for. I personally would just update the map and see how you go. Remember you did do a back up didn't you :-).

The Nuvi GPS are hard to break, software wise that is.

Regards

Col

yes backed up GMAPBMAP, GMAPPROM, GMAPSUPP and I am using an unlocked file from this site as I have been tryin to learn how to do it from scratch although with no luck as I haven't been able to find a dumb dumb version of how 2 I had managed to unlock and transfer 2010 on my own but I have lost or deleted the how to I had for that.

Also the Pre Loaded Map - GMAPPROM.IMG can this be over written with say Supplementary Map - GMAPSUPP.IMG by simply renaming it to the fore mentioned as the Pre-Loaded Map would be 2009 and is outdated anyway?

Hi Again...

To create an gmapsupp.unl you need the following...

Jetmouse keygen - (available from this site/forum)
Your Unit ID - (spanner, settings, system, about)
Map ID - You should know this, as yet you havent told us what map it is!

Run the Jetmouse keygen, enter your Unit ID in the top box
In the bottom box (Select Map Product:) Right Click and select "Custom Mapset" Put your Map ID in.
Click Generate
Copy the generated code into a text document.
Rename the text doxument gmapsupp.unl

Copy the gmapsupp.unl into the Garmin directory.

Now some of the newer Nuvi GPS the above does not work, and the Nuvi 250w is one of them.

Do a search on this site or Google "GarminUnlockerAlternative_v2.4" and follow the instructions included with the Alternative file".


As for renaming GMAPPROM.IMG to GMAPSUPP.IMG, why don't you give it a go and let us know. :-)

Col

Thanks for the info if I was to try the rename what is the worst case ps it possible to kill the unit? Also for the record the maps I am using City Navigator North America 2011
Just qurious as the gmapprom is 1.05g and the Canadian / US, map will not fit as supp due to units storage space

I dought you will Kill the unit as it's a map change NOT a firmware update.

If it does cause a problem, simply hook up the 250W to your PC and delete the offending file.

As I said previously, the Nuvi GPS range is really tough.

Time to experiment!

Col

I have the same problem... Please, let us know if that option of renamig the new GMAPSUPP.IMG to GMAPPROM.IMG and placing over the old one would solve the problem..
Thanks

Prom and Sup image map files are the same.

As previously stated...

Prom files are the preloaded maps on the Garmin GPS
Sup files are loaded from Mapsource.

They are the same maps.

Try experimenting guys.

I did and learned a lot. I am not an expert, just a keen hobyist.

Regards to all

Col
Sydney Australia

OK so my Nuvi 250w is considered the Canadian version so I tried to over write the pre-loaded with the Canadian / USA/ Mexico as well as the Canadian /USA supp image which was re-name prom but unfortunately did not work due to size limitations which is slightly disappointing as I would have like to have the Canadian /USA at the very least perhaps the other individual in the post may not be limited in the same manner as I am.

To over come the inbuilt memory limitation use a SD card.

Make a directory on it called garmin , copy your map into that directory and away you go.

All very easy.

Regards to all

Col