[BigAls87Z28]

I dont understand most of it. You an buy code scanners for the majority of vehicles, and most shops have a basic code scanner.
Now, not everyone wants to spend a few hundred or thousands of dollars on an All-Data system or equiv just to understand how to fix the problem. This is going to be more to do with DIY people then shops. If everyone had to go to a shop to perform thier own service, then I wouldnt be sitting here, typing this on the computer at work with nothing to do.
There are even problems with regular maint. intervals. While we have the info as to what needs to be done, on some cars I cannot reset maint lights on a lot of newwer cars. We do have a service that tells us how to reset 96% of the lights, but some require certain tools...meh.