Hey everybody I'm hoping some one in here can help with my Quandry.

In my '94 the A/C compressor would not come on unless I turned it on via the A/C switch.
In my '06 the A/C compressor pretty much runs as long as I turn my fan on. Even though I live in Az I do not need the A/C on all the time. I'm hoping that somebody can tell me if putting an inline switch, cutting into one of the 2 wires that connect to the compressor, would be a 'GOOD' idea or a 'BAD' idea?
I would like to run the fan and yet keep the A/C avaiable, I currently just unplugged the compressor, Also which wire would be the better to splice into?
I'd sure like to save as much gas as possible, and driving the compressor any time I want the fan on just seems wasteful. Thanx.

 

Running the AC compressor routinely will keep the seals lubricated. I suggest
leaving it as is. Driving habits will affect gas mileage more than disconnecting the AC compressor.

 

The compressor will come on with any setting except for VENT ONLY, and FLOOR ONLY. They started this... late 90's?

Reason being that well 1> It's not healthy to go all winter without turning the compressor on... and 2> Having the compressor on greatly reduces window fogging while using the heat, as before the air is heated it is cooled by the evaporator which eliminates most of the moisture in the air. Being as the ambient temperature outside is much lower in the winter, the A/C pressures run much lower, so the compressor doesn't "rob" nearly as much power as it does in the summertime.

Hope this helps.

 

I just read a study on fuel use with A/C. It was shown (by who?) that 4-40 uses a lot less fuel than the A/C. In AZ you don't need the dehumidification, and it doesn't rain that often.
I disagree about putting a switch in the clutch circuit. I'd do it. If you do, be sure to fuse the line so that the wires you run are not a possible cause of a short toasting your truck. Those wires may just not be routed as well as factory. You really don't have to if you are careful, but it doesn't hurt.
You should check the A/C clutch circuit to see if clutch apply power goes thru the clutch and also sends a signal to other components. Two I can think of are the WOT switch and the hi-speed fan (on electric fan vehicles). Either one of those should not be bothered by not getting the signal.
The seals on compressors have lasted many years as long as the compressor was cycled at least once a month. IMHO, they should be fine if you do that.
On GM cars in the late 70's, you could not turn off the heater fan. Ever. I hated that. My in-laws had a Cutlass that ate its fan motor- it was worn out. I had the fun of replacing it. Thanks, GM.
It doesn't make sense to run a component, even though in winter the pressures are very little, unless you want to run it. Too much loss of control by the driver. Then, again, some people need instructions in their shoes .. "Toe goes in first." heh.
tom

 

Power is supplied to the AC clutch from the N/C WOT relay contacts. And, I disagree, the humidity levels can be high in the winter months in Az. when
you would need the AC for clearing the windows....summer is of course another story....

 

The ultimate mod for a 95+ Ranger A/C system will be to revise the dash switch such that the compressor is engaged in defrost modes and engaged via seperate switch for all of the rest. Check the schematics carefully and maybe experiment with the wiring removed from the compressor before performing the mod; I might be wrong but I thought the A/C system was tied into the ECM (reasons other than WOT cutout?). Would be a shame to do a bunch of work that resulted in a CEL for some goofy reason.

 

I think the ECM will shut off the A/C if the engine temperature rises above a certain setpoint, thus reducing overheat conditions.

 

There is also a feedback to the ECM on most that signals that the compressor clutch is engaged. This is to enable a higher idle strategy. No signal == no hgiher idle.
There should also be a diode in the circuit to defeat the back emf when the coil disengages.
Really need to look at the wiring diagram.
Those EVTM manuals are good, and I even enter penciled "see pg XX" comments when it is hard to find something.
tom