Well with mine, which shouldn't be any different to yours I would attempt to find the latest maps.
Your best source for these is , a site dedicated to all things GPS.
We also have a member here (Bazzle01) whom on occasion steers us all in the right direction.
Have a look in this , I think it's the latest on the subject.
Once you have the maps downloaded, unzip them and place in the CONTENTS folder of your Micro SD Folder
The layout of your SD card should look a little like this.
and the CONTENTS folder a little like this;
Hope this helps
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