My 2008 Sightseer 29R on the F53 chassis didn't have a charging line on the 7 pin connector. Not only that, but the pin that one would normally use for it didn't even have a lug in it, it had a plastic dummy lug in its place. I didn't have any luck finding another 7 pin socket that was fully populated with all of the pins in it that would fit in the existing hole in the bumper so I used another unused pin to run a charging wire from the chassis battery to the towed with circuit breakers on each end. Perhaps they changed that on your newer model.I didn't have any luck finding the 7 pin connector on the Winnebago wiring diagram for for the 2011 Sightseer 35J. Good luck.
Al
Al and Deedee
Spokane, WA
2008 Winnebago Sightseer 29R
F53 chassis w/ JMcKinley CHF and Brazel's UltraTrac rear trac bar
2006 Honda CR-V, Blue Ox Aventa LX, RoadMaster Even Brake