Join Date: Dec 2009
Location: Out there, somewhere
I must have been on the wrong planet for the first few decades of my life. I do not remember any motorhome EVER needing the ignition on or, a 12V source in order for SHORE POWER to work. And, other than needing a fully or, at least semi-fully charged battery to START a generator, I've also not ever heard of the need for any 12V source to keep it running other than maybe 12V for an electric fuel pump.
Now, I'm certainly not the sharpest tool in the shed but, I just can't remember ever needing my ignition in the coach on, to either start or run the Gen or, have the shore power be effective.
Now, I do know that, some, if not most, modern day fridges and thermostats need 12V to operate some of the circuit boards in the controls.
And, I'm certain ALL motorhomes are different but, just how much different, who knows? But, the basics to me are, if you plug in the shore power, 120VAC is now proceeding to and, right through most Inverter/Chargers, right to the 120AC panel which, is then dispersed through all the circuit breakers to the appropriate outlets. Or, if you have a gas coach, the shore power proceeds through the Converter/Charger and, right to the 120AC circuit breaker panel and, so on.
Where, may I ask, is the need for the ignition of the coach, to be in the picture?
There might be a simple answer to the OPs problem but, off the top of my head, it's not coming into mind right now. Maybe there's some sort of major solenoid that has to click into place, in order for the shore power AC to be allowed to go through, heck, I don't know. And maybe that solenoid is triggered, in some odd way, by the ignition, again, I don't know. I'm always learning something on this site.
2004 ITASCA HORIZON 36GD, 2011 GMC Sierra 1500 4x4 Toad '08 GL 1800 Gold Wing
Retired-29.5 yrs, SDFD, Ham - KI6OND
Me, Karla and the Sophie character, (mini Schnauzer)