It's important to be able to turn off the power to the winch so that during a crash, it can't cause an electrical fire. This happened to a Gladiator. On my Gladiator I had a switch in the engine compartment. Is that what you're asking?
Both are excellent questions. I agree that adding an alternator seems extreme for one more AUX, which is why I assumed it was to fix the charging problems some trucks have. But I know of more than one truck with an alternator that does not keep its 12v charged.
Well, they don't seem to know what the hell they're doing. When I replaced the original battery with an AGM on our RAV4 Prime two months after it was brand new, they said that my replacing the battery with an after market AGM caused the battery to fail! BS, it lasted 1.5 years. When I realized, like on the Tacoma hybrids, that the batteries discharge relatively rapidly, I put the RAV on a trickle charger about once a month depending on how often we drive it, and turn off the app.
My wifes Lexus electric does the same thing, and it also charges its 12v from the traction battery with a DC/DC converter. It was a Lexus dealer that told us to stop using the app, and I has not died again since we did that. Her SUV died just one day after it had last been driven and it was only six months old!
I imagine Toyota would work to fix that if they weren't selling so many cars and trucks. Even after I trickle charge my TH, it still is at 4.30 most of the time, just charging away. It seems that the system does charge the battery, but the drain is very high.
