Im wondering is the electric fan in a 5.9 suppose to turn on when you hit the ac button ? I dont think mine turns on because all i hear is the airconditioner pump thingy cycline. I know my fan works tho because it turns on when i reach around 200f.

 

Efans were never stock, so, it all depends on the controller that was installed.

 

The more expensive fan controllers are set up to turn the fan on when the a/c is on.

 

ya you want the fan on when the a/c is on

 

It depends on the controller, if you route a trigger wire from the a/c comperessor to a controller with a provision for it, then yes. It will cool the a/c condensor more quickly allowing for faster cooling of the cabin. Be aware that the a/c compressor also runs when you run the heat as well, so in the winter it may over cool the radiator, and extend the length of time the heater takes to produce heat/give you inconsistant heat.

 

If your in the frozen north it's probably not a real big deal if you don't activate the E-fan when the A/C compressor kicks on in the winter. Summer, yes. Also, from what I've experienced on our 3 vehicles, the A/C compressor will not kick on in the winter until low pressure switch at the top of the accumulator reaches a temp of 30f.

If you look on the firewall behind the accumulator you will find (or should) a tube sticking about 3/4" or so blowing air on the accumulator to warm things up in the winter so that the low pressure switch will activate.

 

YES!

Mine didn't come on and the pressure spiked when the AC was turned on. I had to rewire them to turn on