RV Repair: 12 volt power, popup camper, trailer tongue

Question
We have a 2002 Coleman Sedona popup camper.  My husband and I are trying to get it ready to use this season and in doing so we tried to use the 12 volt battery to check all the lights.  We were not able to get the lights to work using the 12 volt on the trailer tongue, but if we plugged up to house power the lights came on in the camper.  We charged the battery on a slow charge (2 amp) overnight.  When my husband went out this morning the charger indicated a full charge on the battery.  He hooked it up, but got nothing.  He thought maybe he had the wiring wrong, but he has tried all combinations and still got nothing.  The other thing that I am not sure of is if we are supposed to flip a switch in the converter to indicate where we want power to come from.  Any suggestions?

Answer
It sounds like it is in the convertor. Whether it is the switch , or something else, I really couldn't tell.
Your best bet is to call Coleman Customer Service. They can help you troubleshoot it.
They should have a website that you can go to.

Dave