B+ motorhomes

My short , I think it's a short, it acts like one is in the chassic part of my RV not the house part, I was able to start the motor by using my coach battery switch on my dash board. I did have my RV pluged 110v from my garage so that battery is OK. I also make sure the house battery is switched off with the switch by the steps when I leave it . There is definatley something using juice from the chassic battery. I put a Volt meter on the battery after I charged it up and it read 12.67 Volts ( about 95% ) , I left it connected overnight and checked it the next day and the reading was 12.45 ( about 70% ) the next day it read 12.14 , so something is really sucking juice from it. I just returned from Canada so I did not have a chance to bring it back to the dealer , and next week I have to go again so everything has to wait until I return. I am trying to do my driving between snow storms, we just got about 21" of it here in CT Monday. Thanks for your response Dan & Larry.