Hi Joe,
Can’t help much as I don’t have a TMX 100 but I can help with your last question (I know it was rhetorical
).
Actually all troubleshooting is difficult (quite literally troubling) but mechanical systems seem easier because you can see or feel the evidence of a failure (broken rings, play in bearings, grooves in rollers, etc.). You can’t see electricity (just the results of its presence – light, smoke, etc.) so you must use test equipment to make it visible, to “look” for a failure or to confirm things are OK. The test equipment should be used in conjunction with a detailed wiring diagram (schematic) and ideally by a trained person. You probably have measurement equipment for mechanical systems already (a rule, caliper, feeler gauge, etc.) and you need measurement equipment for electrical systems also. A multi-meter is an excellent tool when looking for electrical failures on a motorcycle but you can obtain good information about a problem or any circuit with a simple test lamp and some clear, logical thinking while referring to the detailed schematic. Whatever test equipment you use it is important to practice with it on good circuits first before you tackle any troubleshooting (somebody taught you to use a rule before you made measurements with it). I suggest all motorcycle enthusiasts own a copy of the book shown in the ebay link below as it is an excellent training manual and reference book.
https://www.ebay.com/itm/HAYNES-Repair-Manual-Motorcycle-Electrical-Haynes-Techbook/224319817616?epid=1737365081&hash=item343a80c790:g:Jx8AAOSwcnVgBLYFEvery motorcycle has electrical stuff all over it so it’s best if you do get friendly with it!
A little reading and a bit of a play about with some wires and a lamp should get you going.
Your other questions could be answered by simply observing the schematic diagram (available in the Download section of this site) if this schematic was detailed. Unfortunately the functions of the switch are not drawn, as is usual in many vehicle schematics, so I can only guess at its operation.
Hopefully someone with a TMX 100 will provide the real answers you need.
Best Regards,
Mike Munday,
Melbourne, Australia