I would open up the panel box and see if the dead wall plugs power feed is laying in there disconnected. If it is most likely it was disconnected for a reason, possibly a short? Pull all the dead plugs apart and look for skinned or touching wires, bad outlets, etc. I would get a little brave and try hooking it back up and see what happens. Be careful, if it doesn't throw the breaker don't chant victory, you want to make sure your trailer has a good ground in order for the breaker to trip or else if you touch your trailer and the ground you may become the ground, deadly stuff!!
You may want to consult a good electrician, people get killed by stuff like this.