I would double check Camping Worlds work, I would check for a ground as Bob suggested and then check the wire to the f150 battery by taking it loose to see if 12 volts is there if so then I would check the size wire that camping world used ( perfered #10 but # 12 is ok as most pigtails only have #12 wire in them but some just has # 14) If all that checks out then check the pigtail to make sure they did not hook the charge wire to a #14 wire, generally the largest wire is the middle wire. My owners manual has a warning about a low battery could cause the 4 wheel drive trans to shift while towing and that would not be good.
Now after all that we have had a problem with the F150 battery going down in the earlier F150 , I recently took my F150 in with battery problems for a computer update and they installed a new battery and I was told it was a larger amp battery but??
Walt & Will
2013 F150 XLT Crew C 4X4
2015 Kia Soul 6 speed manual