D3048150A.JCV will not work in xx nuvis, if you have both of those files in the unit's .System/JCV or the card's Garmin/JCV folders there can be interference.
D3589120A.JCV is correct file. What have you done to test it? Try a simulated route from a major city to another along a major highway/freeway/expressway. Nowhere near all interchanges or exits have Junction Views, especially with D3589120A.JCV which is quite a small file so there's only limited views.