fan coming on

I have in the past had bad oil press sensor, bad wire at sensor too, but those times it would throw a code & engine light would come on. I have a new clutch, no air leaks there. I would think maybe a bad wire connection or a sensor, but all sensors are new, less than 8 months old. & I can predict when the fan will come on & go off. if it were a bad ground wire, e.t.c. it would come on sporadically not like it does now. the reason I was thinking pressure switch on the a/c compressor was cause the fan comes on & goes off exactly as it would if I was running my a/c. I remember when I had my bull gear put in, when I picked truck up the fan came on when engine started. the shop mgr asked the employee if he connected the wire from the a/c? the guy told the mgr no cause the a/c/ was not hooked up. mgr said makes no difference the wire has to be hooked up to keep fan from running all the time. he connected the wire back & that solved the problem. so I learned even though the a/c in not operational, the wires still need to be completing a circuit.

 

it may be the intake air. I noticed today while pulling a grade the fan came on at 195 then went off at 200 water temp. when I topped the hill at temp was at 205 & never went above 205 & fan did not come back on. but still comes on for 30 seconds if I am parked with engine off for a couple hours & engine temp at 150 or so.

 

the 2 wires that go to the pressure red top switch in line with one of the hoses that go to the condenser, if I cut those wires & connect to each other would that stop the fan from coming on? there is no condenser on the truck. the hose is cut & is about 6 inches long just laying on the a/c/ compressor with the wires attached.