Why does MAPS app just show grid lines and not streets and labels?

I have several older 3G and 3GS iPhones that I purchased/picked up for repair and resale however everything works fine on them except the MAPS app. When I launch the MAPS app it just shows a blank page with grid lines and the blue dot for location. But In the satellite mode it shows the correct overview of houses at my location. Does anyone know if this is a software or hardware issue?

Note- I have several other 3G/3GS that DO show the correct MAPS view with streets, names, and labels but most of the units do not.. On the units that don't show the correct view I have restored them to factory settings several time, connected to WIFI, and have the date and time set to automatic. My understand is the data for the streets and labels comes from the internet but nothing is coming over even when connected to iTunes and/or WIFI.