I'm probably not the only one who has no idea what your talking about.
What kind of control box?
What is "H"? What is "X" what screen?
Manufacture? Model number?
You probably want to looking into driving a triac. A triac is like a relay but can be switched much faster. It is the heart of a common dimmer used in household circuits.
Need more details of what "something else" is.
A good place to start would be to look at the power rating of the original light. You know it puts out 12v, but we don't know the maximum current its capable of delivering.
No. Not to my knowledge.
As long one is in control of their vehicle, insurance should not be impacted by it. Of course, I could understand a claim being denied after a fire if there was obvious signs of improper wiring, but most insurance companies would likely not even bother to investigate.
If they are confused by the technology, they would also be confused about modifying their cars circuitry.
I would hack my own car, but no way would I ever modify someone else's car.
Maybe, lol.
The motor label tells you how to hook it up, but a qualified person still needs to figure out the unidentified wires (armature/field)
Based on the black carbon marks on that one wire, it looks like it was already hooked up wrong?
I hear you!
Codes and standards are constantly changing and a struggle to keep up with.
As a master electrician one of the hardest things for me is to try and forget older codes and adapt to new ones.