I just bought a 2010 lakemaster for my lowrance ifinder phd, and when I put it in my gps it did nothing. Any tips?

Dont you have to select what map you want to show from the map data menu?.. dont know about your unit, but with the H20 you do..

did you make sure the map is compatible with the gps?

You need to go to the map data menu and ensure that you are not on the lowrance base map.