What electrical school did these people go to?

I just had to replace the 7-pin socket on my TV and had forgotten my voltmeter. So, I thought, I'll just go by color codes. WRONG! Thankfully, we were in a Walmart parking lot at the time (our storage place has gravel drives) and my wife went in and bought a cheap meter.

The idiot who wired this up must have worked exclusively on AC electrical systems because the 12V and ground wires were black and white...respectively! So, thinking black was ground, as on every other DC system I've dealt with, I proceeded to initially wire them backward. If it weren't for the voltmeter telling me they were backward, I very well could have done some serious damage when I plugged in the Pod.

I'm happy to report that everything worked as it should.

I printed that etrailer info and carry it with me. The 7 way RV
standard is exactly the way mine is wired and black is indeed 12V and Ground is white. A 7 way standard trailer plug is different. We just had a similar post where bad info was being provided. Another example - in trailers brown is normally tail lights, 7 way RV standard it is green.

Bum, I cant answer that, but mine is not wired that way. And it matches a 7 way RV Standard. Real quick you can check by looking at you fender wires, is it brown there? Mine are green. The yellow is the reverse light wire. That's why I use a simple 15 amp test lead with two spade plugs, I can go from 11 o'clock 12 v to 1 o'clock trailer taillights looking at the end of the trailer plug and ensure lights are working. I don't need a TV to do checks. I do agree you need a DVM to ensure you are looking at a the right stuff and I think even the etrailer guide says wiring color does not apply. I can go from the 11:00 12 volts to the center and my add on reverse lights work. My brake controller is purple at the 7 position, and I have nothing blue.