HELP 2013 pete 386 w/ cummins isx 15 clutch fan on and off

the fan clutch goes on and off, on 1 min off 3 min, is erratic sometimes staying on for long periods of time before shutting off, I have replaced hi pressure switch at a/c compressor, fan switch on firewall also low pressure switch on fire wall, also replaced coolant temp sensor connected to ecm , and replaced fan clutch solenoid on firewall ,fan clutch has no air leaks and relay checks good, problem still exists, can anybody help

 

Take it to a shop.
Your wasting a bunch if fuel if the fan is always on. Probably a solenoid.

 

Go to a shop.
Could be a solenoid.
You are wasting fuel.

 

I'm having the same problem on my 97 n-14. Haven't had a chance to get to the bottom of it yet.

If you figure it out , please finish up with the thread.

ECM problem possibly ?

 

fan clutch could be failing. check the pins on the 2-pin connector to the solenoid, make sure they are not all loose, you should be able to stick the end of a paper clip in and have drag in and out, if there is no drag, replace pins or whole connector .

 

Just trying to keep it simple, so first I would hook-up some A/C gauges to see if your head pressure is spiking, meaning it very well could have been over-serviced causing the fan to operate more than it should, if readings are normal than the air line to the clutch or to the solenoid are bleeding off somewhere, I guess a third possibility could be that the switch located in the H/P line closest to the compressor (kicks on the fan for high A/C head pressure), might have a wiring issue or again a bad "new" switch as you state.

 

Throwing parts at something and hoping it fixes it isn't a smart way to do things. Almost everything on modern trucks is run through a computer. You need to see what it sees. Could be as simple as a plugged up rad causing high coolant temps or A/C pressures.