You'd Pass -

ie having seen some of folks' IT test question suites here, I'd add that this exact home scenario figured on some of my Q/As for newbies. (Yeah they were supposed to grok 'electronics', but often enough, brain would freeze on the much simpler 'electrics'.)

Much worse today, I hear - many EEs have never built anything that needs a soldering iron, relying on *%&^$ computer-simulation for all courses. Then when they find out what happens with all those ground currents circulating inside the 6+ layer PCBs ...

Right answer: when wiring is uncertainly marked == according to a clear code, in the end you save more time by verifying it exactly this way. Even if it seems silly to run a long wire for a 'test lead'. A simple ohmmeter will answer the questions.

(There's a roll in my trunk, too -- often needed in modern cars, where a bad >one< of the multiple [Grounds --> body, all over the place] can really screw up modern computerized toys: with phantom power/pulses appearing in places that the cookbook flowchart knows Nothing of. So.. save that test wire! :-)


I'd like a $_ for every time this suggestion was followed by..

A) too much trouble
B) hours later.. finally does it and finds out, OR
c) call$ electrician


PS - another use for that coil of wire you got, from recent experience at a car venue:

Most modern cars (even my '94) have extensive starter interlock chains.
It's difficult to sleuth these by LED light at 3 AM. after a bit of Absinthe.
You don't know if your starter has died or.?. some part of this chain, but you want it to START.

One end goes to battery [+] == after you've found and gotten to the solenoid's terminal (not the Hi-current connection.) Without a clamp on one end, it's a bit of a PITA if alone; else - you hold an end on the solenoid terminal and assistant touches the other end to battery [+]. If starter doesn't turn Then, you're screwed.

(Note that, with IGN ON: car will indeed run, unless something else is broken.)