Often I am asked why the Big Five manufacturers don't make their owner's and service manuals available online. The fact is, they do. Sort of. Most of the Japanese OEMs at least post their owner's manuals on their public websites for consumer download. As for service manuals, Japanese OEM dealers have to pay for the 800+ page manuals, even though they are electronic. For that reason the manufacturers don't make these same files available to the public. It would be against the dealer's interests. Historically of course it has been observed that some dealer somewhere will eventually hand off one of the electronic files to his customer, and the manufacturers, though not in favor of that, are not in a position to prevent it. Thus eventually the service manuals make their way to the Internet for mass consumption.
One thing many don't realize about electronic service manuals is that in most cases they are updated when errors are discovered or other changes are needed, on a much more frequent timetable than are paper manuals. This is a good thing for the dealer, naturally.
I have said much elsewhere about factory service manuals, including how their creators, the manufacturers, view them. Check that out on my website.