We've bin to florida this year and bought a tom-tom via 1605 device with a USA and mexico map on it
is it possible to set it to western europe
the info on the tom-tom is

device wn3442f01101 (0) (24.1)
app 12.071.1370596.94(0) (2092, 12-9-2013), os 1344689
gps 2.18.903 127792, boot 865401, backup 889478
complaint with the nf mark / product certifié bf-469
card 'USA_canada_and_mexico v925.5413 releasedate 2/2014

thnx allready

You can but you'll have to buy the map you want through TomTom themselves:

tutorials-f80/important-note-for-new-tomtom-models-like-via-start20-go1xxx-please-read-t8690.html