+1 for the basic level of knowledge. It's easy for the uninformed to do damage to the electrical systems, or themselves. If you play around with the plumbing and mess up, water escapes and you get wet. With electricity it can be much worse...
I caught the 455, very good statement. I'm not interested in debating with a friend/neighbor how to do or fix something if within the first five seconds it becomes apparent that they get bread stuck in a toaster out with a steel knife while it is still plugged in.
Every educational link is a worthwhile link - but I cannot help but wonder how many browsers read these threads for entertainment? I have no valid complaint of they elect to not take advantage of this stuff.
But if they return with "The blue wire is for what and does it have electricity and how do I know and he said she said..."
Way way way back when Delco introduced their first selenium rectifier AC generator and I took the earliest model Leece-Neville alternator into a rebuilder and he bungled the test I realized then one out of fifty people who swear up and down they know what they're doing -- actually are "accurate".
At age 60 I had to educate myself about light emitting diodes, because there was enough B.S. floating around to start a fifty acre hydroponic garden.
Some folks have zero mechanical aptitude to begin with and stacking electrical theory on top of that makes it illogical they would even consider tackling electrical diagnosis and troubleshooting.
So my theory is this...
Inform them going into a self-repair they need a test light and meter. If they balk I balk. Counter reaction.
"Hey neighbor! Know anything about yanking a 455 Chevy out of my 37 foot motorhome? Not that big a deal, right?"
For "masters" at using a 12V test light check out Eric O. on the YouTube South Main Auto channel and Ivan on the Pine Hollow Auto Diagnostics channel. These guys know Ohm's Law inside out and backwards !
One tip, always confirm the test light is properly functioning. You never know when a loose ground on the test light can send you off on a wild goose chase.
Most test lights are about 30-50 ohms. This means that at MOST the light should only draw 400 mA (typically, more like 250-300 mA), so most computer controlled outputs should handle that current. Don't forget, 99% of computer circuits GROUND the control side of the "device under test" !
Mex That is a very good Test LIght and .. Yes. it's my first GO TO Item when tracking power faults (Mine is not as nice though)
VOltmeter (Mine vary I have several) is #2.
Home was where I park it. but alas the. 2005 Damon Intruder 377 Alas declared a total loss after a semi "nicked" it. Still have the radios Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times
I have a Thor Vegas that the Generator switches in the unit work when they want to. I have all the equipment and extensive knowledge but still cant figure it out. Here is the best part, Thor has no schematic on any of their units.