Question on Battery Disconnect

dpgllg wrote:
I believe the tech that did our delivery stated that slide 2 will still function even if the power has been disconnected. Could just having this feature cause the battery to drain?

No.

Could there be other things such as the CO2 detector etc. still connected? How can I tell?

Sure, depending how your Grand Design was wired. Anything that represents a continuous parasitic draw will eventually kill your battery. Call their tech service and ask how yours is wired.

Can I install another disconnect that will totally kill all power?

It's your camper, you can do what you want. ;) Many of us do install our own battery disconnect switch that kills power to anything we want. In my case, I've chosen to wire the tongue jack directly to the battery but everything else runs through my Blue Sea Battery Switch. Some would prefer to also have the brake system's breakaway switch wired directly to the battery but I chose to run it through the switch as I always have the switch on when towing anyway. Your choice, wire it to do what you want. ;)