@Junko: How about contacting Toyota in Japan? They may be better to answer our curiosity.
If most renowned organizations are not involved, than it is not international standard. May be at latter stage they will modify and make it IEEE standard. Many US organization does follow this practice.
Mhrackin: Oh, now I remember all those old bad movies where some American spy is tied up by bad guys in some Central American dictatorship and they attach an old telephone ring device to his, um, elbows and start crankin'. Yeah. That looked pretty painful if that's what we're talking about. I guess it's a good thing they put the little trap door on those phone plugs (sigh).
One practical reason for standardizing car power components is to enable emergency services to rationally deal with the guts of a car in an emergency. Today the high voltage high current wires on hybrid cars are fat bright orange wires - not the place to apply cutting tools. Perhaps there are some more mundane conventions that would be nice to standardize so that emergency personnel (or garage mechanics) don't have unwanted surprises on vehicles with which they are not already familiar.
When I was in high school, I took advantage of the 86 VAC telephone rung voltage to trigger a standard 1/4 watt night light as a silent phone bell that wouldn't awaken anyone late at night (I turned off the other bells). Having my fingers on the terminals of an open phone when it rang did give an unpleasant jolt.
For obvious reasons, I'm with Junko on this. I think we are fortunate to have the press (well, what's left of it) to find out the things that companies don't necessarily want us to know. I think that's the whole point. Waiting for companies to tell us what they want, when they want means we will be a lot less informed.
I forgot to mention one point: at 20Hz, the body's response is much more painful than the same shock @ 50 or 60 Hz. The frequency response of the nervous system makes the muscles contract and relax at the 20 Hz rate, so you do get more "all shook up." 60 Hz is considerably attenuated.
Working in telecom for many years, I've been "bitten" by ringing voltage a few times; it's relatively mild, but not particularly entertaining. It reminds me of Mark Twain's comment after being tarred, feathered, and ridden out of town on a rail: "If it wasn't for the honor of the thing, I'd of just as soon walked."
mhrackin: You were indeed a brilliant EE at an early age! It wasn't until I was in my 20s that I did something similar with a screwdriver while trying to remove the plate surrounding an outlet. Clearly, I was not intended for a life as an engineer.
Would anyone else like to fess up to a shocking experience?