[Richard]

A voltmeter is your friend in answering this question. Newell may have changed over the years but on my coach, that is a buddy plug. It provides power to the plug when I am plugged in or running on the generator.

I would measure the voltage at the plug 1 when the coach is plugged into shore 2. when the generator is running 3. When the coach is unplugged, without gennie running, and on inverter power. The answers will tell you when the plug is powered.

I would not plug the coach umbilical into the buddy plug without checking the above on the buddy plug first. In theory it shouldn’t hurt anything if is isn’t a buddy plug, but a cautious approach is good lest you let the smoke out of something electrical.