since I work at a dealer and I am a tech I have access to fmcdealer.com I can access all the service manuals including wiring diagrams and pc/ed books online. plus I get oasis acces from there and other cool stuff
anybody who works at a dealer has fmc access but it is limited to your job role.
parts guys have part related stuff they can do, salesmen have tools related to selling cars. dealers and higher up managers can order equipment and special tools on that site.