Considering how far electronics has come in just the past 50 years, one wonders what sort of repair questions technicians of the future will face. Stuff that's as common as beer cans now may be extinct just a few decades down the road. Repair techniques we now take for granted may not work on tomorrow's equipment. Think about it; we may have to deal with bioelectronics, teletransportation equipment, tech support between planets.
Schematics may become so large as to be unprintable on paper, or even stored on even one mass-storage device.
The vast majority of electronic devices may be impossible to take apart, much less repair. (And some manufacturers may not even bother to print part numbers on some components as a result.)
Microscopes will become absolutely necessary, as will lasers for spot-welding soldering.
Will tomorrow's matter-teleportation devices come with any warranties? Today's software doesn't.
In the early 1960s, _Mad_ magazine printed a funny article called "Future Complaints." It illustrated the potential problems that people in the future would have to deal with. Interestingly, some of these gags have indeed not only come to pass, but become obsolete: a customer in a super-fast photoprocessing store was angrily complaining to the helpless clerk, "What do you mean, 'They're not in yet'? I brought them in over an hour ago!" But the funniest one was still this: "Geez, can't they do something to speed up these long lines at the post office?"
So use your imagination: What will technology be like in 50 years, what will break down, and how will we fix it? What tools will we need? We technicians may find ourselves having to repair clothing that comes with data-transmission capability; having to remotely repair I.D. chips beneath human skin that have stopped working; repairing or reconditioning biomedical devices after they've been retrieved from people who no longer have need of them. What else?
Whatever we build, will eventually break. You want your jet pack shutting off at 1,000 feet? :)