How about a electric fan ac compressor question?

[348tripower]

So I found that I really should be running the electric fan on the wagon when using the AC. The high side over pressures with out enough air over the condenser.
I have a o ring binary switch on the dryer so swapping in a trinary with out loosing charge is a problem.
I had run a fan wire to the console for a aux switch to run the fan before the controller starts it if needed.
So I tied into the compressor wire 12v to run the fan relay when I turn the air on and now when the fan starts thru the temp controller without the air on  the compressor runs too.
I am considering a diode in the wire from the fan?
Obviously it is back feeding like an alternator will to an ignition switch. I have those diodes in stock.
Or I put a shrader valve fitting in the high pressure side of the system. Maybe add the trinary there?
Thoughts?

[enjenjo]

You can do either, but the diode is cheaper.