Truma Mover SE/TE caravan manoeverer, 2007

For manoevering in confined spaces, single-handed, via RF R/C hand unit Assuming no one would happen to have the schematic for one. Would anyone know what the safety logic/inter-lock around the swivel-out/in motor systems is. I understand it makes sure the caravan cannot be driven off while these drive units are positioned against the caravan wheels, somehow connected to the caravan brake light wiring. Also what to look for in the way of overcurrent to those motors (or even the main drive motors) as there sems to be no predetermined positioning of the swivellers but seem to move out until some sort of good contact with the tyres is made.