2001.5, air cond runs all the time,I have to turn the bottom control **** on the dash to adjust the cool/heat, this is normal but the compressor never shuts of no matter where I switch the top ****,be it on any setting to send the air out of any outlet, seems to me it used to cycle off and on,I have lots of cold air, no problem there, I can have air-cond out of any outlet, dash,floor,defrost, makes no difference,Is this a contstant running air-cond system or is it supposed to cycle? If its supposed to cycle I suppose the control module in the dash is toast and my understanding is one has to buy the whole unit,no parts available,I checked the price, $225.00 from Dodge.

 

if your switch is anywhere but off, the compressor should be running. actually the compressor should never cycle, the only reason it does is if the system is out of its proper operating range. low psi low, compressor cycles, high psi high, compressor cycles, in a proper system it should never have to cycle, seem like you got a good running system, mine operates the same way and man it blows snow.

 

I can say that the AC compressor should run while in AC Vent, Max AC, vent & floor, Defrost, and defrost & floor. When in vent only, and floor only, the AC compressor should not run.
Check carefully to see if the compressor is running in the two selections where it should not be.
The compressor will cycle normally when it brings the low side down to a certain pressure, which equates to being cold enough coming out of the vents. As the heat is exchanged inside the truck the pressure will rise on the low side and the compressor will caycle back on. This is normal behavior unless the compressor is cycling rapidly, as in 2 seconds on and 2 seconds off. When it cycles the compressor should remain off for 5+ seconds before it comes back on, and should be on for more than 5 seconds. The on time will usually be much greater than the off time. These times vary, but should give you an idea if you are cycling too much.

Chris

 

The compressor DOES NOT cycle at all,it just comes on and stays on continuisly and the compressor runs at all vent selection settings,the air is ice cold,even a brass monkey wouldnt have a chance.........

 

Correction to my last post,yes the compressor DOES shut off when the selection **** is on vent only and floor only,all other posistions, compressor runs continusly,heres a little more info,a week ago the air wasnt cold any more and the compressor was cycling on and off every few seconds so I put some freon in till it was nice and cold and now it dont cycle at all any more but its as cold as anyone would want it to be,I was under the impression that this system did cycle on and off but maybe it dont,you know how it is,when everything is working ok one maybe dont pay attention to the operational aspect of it, one maybe thinks after its working again,is this the way it always worked or what, as in this case was the compressor always running or did it cycle, of course it cycled when I was low on freon and now it dont but I will say it never cooled as good as it does now.If this system is supposed to cycle I was thinking maybe I put a little too much freon in it and it wont pull the pressure down so the low pressure switch will cycle it off. I do have a off and on switch that I installed,(the 98.5 and up didnt have a off and on AC switch like the older ones) so I can shut the compressor completly off if and when I want to, no point in running the compressor when the weather is such that the heater is on, works great.

 

Rev your truck up in neutral. The high pressure switch in the system will disengage the compressor. If it was not disengaging the a/c lines will ice up.

 

OK, depending on the temperature outside, the compressor may continuosly run. When it is hot that compressor will always run while the dash selector is in a position where the compressor should run. In a case where it is cooler, the compressor will cycle, when the dash selector is in one of the positions where the AC should run. Most of the reason this is done, at least for the defrost positions, is to dry the air so the "defog" will work faster on your widnshield. Why it works on the vent and floor position I do not know. I guess Chrysler thought that woul be good.
I much prefer my 96, which has the fan selector that either goes to the left, for fan and AC, or to the right, for just fan, so that AC on/off is independent of the vent settings.

Chris

 

whole lot simple arnt they

 

you put in to much freon.let some out.

 

For a real simple answer, yes it should be cycling in normal operation. And it should not run in vent mode. It runs in all modes with the snowflake plus bi-level which does not have the snowflake for some unfathomable reason. check the control relays.