Do you usually look up the basics of what to do before you begin, or just start tearing things open?
My favorite line: "Yeah....I have no idea what this thing does..."
The schematic for a variable speed ceiling fan is actually kinda complicated - as it turns out. Maybe someone with a more advanced electrical background could chime in, but I think that thing was actually a transformer that alters the voltage to provide varying fan speeds.
I went into this figuring how a pull-string might work, and when I had the assembly apart figured out how each moving part functioned to get the overall effect of moving the chain out and back in. It would have to use a spring or some kind of tension device to put the chain back into position. But, nah, I didn't look up a ceiling fan repair or anything for this.
Looking stuff up really depends on the project.
If it was more involved, like the actual fan motor, I would have probably looked up the basics on how the ceiling fan motor is mounted, and maybe how to get to it etc... I'd assume from the start that it was a basic, run of the mill alternator AC to DC type set up. I wouldn't go so far as recoiling wires though. It's just much easier and time saving to just buy the part in that case and replace it.
For the car door, I looked up some Subaru forums on how to pull off the molding. Usually with cars, someone's already done the work and knows where all the tricky screws and problem spots are. This was especially true when rebooting the ECU.