Generator charging car thru the Ollie?

I accidentally ran across an interesting event and wondered if some of you electrical wizards could help answer some questions.

I was powering the Nest Egg with the Honda generator set on eco throttle. The car was still attached to the Ollie. I went into the car to "crack" the windows a bit and when I turned the ignition on I could hear the Honda revving up. Wondering if was just a coincidence, I did it again with the same result.

Questions:

Is the Honda trying to charge the car battery or is it just powering the systems?

Is there any danger in this? (small gauge wires, blown diodes, etc?)

Could this be an emergency way of charging a weak starting battery?

Any and all help is appreciated. BTW, there appears to have been no ill effects to either electrical system, but the ignition was only left on for a few seconds.

Aubrey,

My understanding is that it is not a good idea to maintain the electrical connection between the tow vehicle and the trailer for any extended period that the tow vehicle engine is not running, such as while you are enjoying yourself in camp, unless you have a battery "isolator" installed, to prevent the trailer's electrical needs from depleting the tow vehicle battery. The situation you cited is the first I have heard of where the tow vehicle is apparently drawing from the trailer's batteries, as evidenced by the reaction of the generator. But it stands to reason that the electrical draw could go both ways, without the isolator.

More experienced RVers than I may be able to answer your questions regarding whether there is danger to your tow vehicle's electrical system and whether you can charge your tow vehicle's battery with a generator hooked up to your trailer. In any case, I would advise unhooking the electrical connection between the tow vehicle and the trailer when you are not actually towing, to make sure that you still have enough charge in your tow vehicle's battery to start the engine.

Steve

Not knowing any better, I had the Nest Egg continuously hooked up to the car for almost a full month and sometimes went 3 days with no AC power at all. I never noticed any weakness in my starting battery so I'm guessing (read: "hoping") the smart charger protected it as well.

Ignorance is bliss. Well, sometimes anyway.