Isuzu Mu7 Sat Nav SD Card

[Greenside]

The built in sat nav in my Mu7 has stopped showing the map detail although it gives the right co-ordinates so I'm thinking maybe the SD card that holds the Garmin data has got corrupted.  Does anyone in town have a 2012/13 Mu7 and would be kind enough to let me copy their card to see if that's the issue?  Isuzu wants to send the whole unit to BKK for a month which I'm not keen to try as it means no music, phone or radio, not to mention a gaping hole in the dash that begs to be used as a postbox by the children.