Hello Rick,
Welcome to iRV2, we're really glad to have you here as a new member and are looking forward to reading your posts about your RVing experiences and adventures in your 2004 Trailite. You'll find a great bunch of folks on this site who are
very knowledgeable of RVing, the rigs we use, and the places we go in them.
Test the DC voltage when the slide switch is activated, if it drops a considerable amount from what the voltage is at the battery, you may just have a weak battery. If there is not even a slight drop in voltage then you might check for a tripped DC circuit breaker or a broken electrical connection. There are several other possibilities but these tests should get you started.
As you'll see, members are eager to help and share their knowledge and experiences.
Again, welcome to iRV2, we're glad you joined. :wave