There is a diagram... Now depending on the make and model of your RV or vehicle the odds are likely in the 90% or better range that a standard CHLITON's or other manual applying to the chassis your vehicle is based on will apply.
I think Chiltons's makes a Air Conditioning manual.. Colors may vary from vehicle to vehicle but the basic diagram is the same and there are but two
One has a switch (that's in the dash) which MAY operate a relay.. Either the relay coil or the power to the compressor also runs through a sensor or two.
Other than the clutch winding (A magnet) Not much I left.