So far so good, everything is working normal since plugging the trailer into electricity last night.
So I guess the battery was running low and needed to be charged.
Don't know if the battery was fully charged when we picked the trailer up or not ( we are assuming it was).
The trailer was delivered from the factory to our dealer and we picked it up the following week, so it is about as new as it can get.
We have only had the trailer plugged in a few times since we picked up and even at that probably not for more than 15-20 minutes at a time.
We also have never shut the battery disconnect switch off, so after we leave it connected to the electricity for a few days we will try shutting off the battery.