RV Repair: transfer switch, tioga arrow, capable woman

Question
I followed the power cord on my Onan GenSet4000 EmeraldPlus, but couldn't locate any transfer switch to get power inside my coach! I have a 1992 Fleetwood Tioga Arrow (Ford E-350) When I plug into home everything in coach powers up, including outlets. However, when I start up/run generator, nothing powers up at all!Plus I notice that the interior lights work regardless if generator is on/off, should that be? Further more, when I am pluged into home and turn on the RV's overhead Coleman A/C the fan works on eny level, but when I move the switch to A/C the breaker instantly pops! On a couple of occassions I was able to get s/c to actually come on at the low speed yet within 2minutes the breaker blew. This happens at any time of day/night. I am a very mechanically capable woman whom has rescently lost my job and have become homeless, unable to afford a technician or shop, so what and where do I start to test?

Answer
ok follow the power cord into the coach inside the compartment where the cord goes is there a plug in that you can plug the cord into.
yes the lights are 12 volt they run off of a battery
when it ran for a couple minutes on ac did it make any noses or kinda shake?