The propane detector is always on, using 12 volts... It will kill your battery between chargings if you let the Pod sit for a few weeks.  A lot of us here have installed battery disconnect switches to prevent that.

 Otherwise you should keep the converter plugged into 120 Volts at home to keep the battery maintained. 

 Letting the battery drain to very low levels, WILL shorten their life expectancy. If you regularly recharge before the 70-80% threshhold, they will last YEARS. Always bear in mine to check the electrolyte levels (water levels) and check the cells with an acid tester bulb once a year.

So yes, check the battery, and make sure your tow vehicle is charging that battery when you're underway. There are approximately a half million posts on tow vehicles and charging on this forum so as Luv2Q says, use that search function and let us all know what the problem is/was.

We all want to learn how you attacked and fixed the problem. That's how we all got so smart. Ha.

If you're running the fridge on battery all that time between trips, that battery hog will for sure shorten your battery's life. Stop doing that right now and switch the fridge to propane.

Sounds like it's about time to get familiar with the site's nifty search capability.  Click on the Search link at the top and select Advanced Search.  Then fill out the form as per the following, and then click the 'Start Search' button.  PS:  Don't miss the stuff on the right side of the form.  You may have to scroll to the right to see it in the image below.

Hope it helps.  You'll find a lot of discussion on battery disconnecting and, if my memory's any good, there are some pix of some installs various members have done.  Good luck & have fun (searching's fun .. you can find an amazing amount of info on different topics).