Another 2000 Ranger A/C Problem
 

I have a 2000 Ranger with 3.0, only had this truck for 3 weeks and the A/C has been working good. Yesterday, I turned on the A/C and nothing, fuse #1 under the hood is good ( 10A ), I have not checked the A/C Relay yet ( #2 ), but I have read there is a WO throttle relay which I cant find, or is the same as relay 2 ? any ideas ?:confused:

Re: Another 2000 Ranger A/C Problem
 

There is no WOT relay anymore since the PCM already controls the AC compressor relay. When you put the AC on, does the compressor engage at all? If so, is it short-cycling on and off quickly or is it running a normal cycle and just not getting cold? Check the relay by swapping it with another one in there.

Re: Another 2000 Ranger A/C Problem
 

The compressor does not engage at all, and the electrical plug is seated good. I will check the plug in the morning to see if I am getting power, are the two wires pos. and neg. ?

Re: Another 2000 Ranger A/C Problem
 

The plug on the clutch is just +/- 12. The clutch failing is pretty rare, in fact I've never seen anyone here have that problem. Usually it is the relay or the low pressure switch.

Re: Another 2000 Ranger A/C Problem
 

Where would I find the low pressure switch ? and is this for low pressure on the freon ? two days ago it was cooling fine.

Re: Another 2000 Ranger A/C Problem
 

It is what tells the compressor to shut off when the evaporator coil is cold enough based pressure. If the switch goes bad, which they do, the compressor will never run. It is somewhere on the low side pipes returning to the compressor.

Re: Another 2000 Ranger A/C Problem
 

Thanks, you have been a big help, I will check to see if I am getting power to the compressor, if I am not, then I will go to the relay and go from there.

Re: Another 2000 Ranger A/C Problem
 

OK, this morning I started from scratch to find out why the AC is not working. Fuse #1 for the AC relay is good, AC relay #2 is good, also tried relay #3 in its place, NG, pulled the connector from the AC compressor and put my meter on it, with the truck running, and the AC on, no power at the plug for the clutch. Anyother ideas as what to try or look for ?

Re: Another 2000 Ranger A/C Problem
 

Just tested the compressor clutch, it will pull in with voltage applied direct to it, pulled the AC relay which I already tested and put a jumper in the socket and the clutch pulls in, but with the truck running, and the jumper in, no cold air. I guess I must have a leak in the system, unless there is something else I am missing.

Re: Another 2000 Ranger A/C Problem
 

Wait so the compressor is running when you jump the relay? What pins of the relay did you jump?

Did you ever check your low pressure switch like FireRanger said?

When an A/C system quits so quickly its usually an electrical failure.

Re: Another 2000 Ranger A/C Problem
 

With the truck running, I put the jumper in the relay socket and the clutch pulled in. There are only 4 pins being used on the relay, 2 for power and 2 for the relay that would close if everything was good. I checked the low pressure switch ( at least I think it was the right one ) , right next to the refridgerent service pipe, pulled the plug and jumped it, no dice.

Re: Another 2000 Ranger A/C Problem
 

I would put a gauge on your lines and see what the pressure is.

Re: Another 2000 Ranger A/C Problem
 

Right now I do not have a AC pressure guage, will try to pick up one this week. From what I can find out, the pressure should be between 30 and 50lbs. correct ?

Re: Another 2000 Ranger A/C Problem
 

I think that maybe right. The gauge should have it highlighted in green. Note you should take the readings when the compressor is on.

Re: Another 2000 Ranger A/C Problem
 

The problem is almost solved, I picked up an AC guage and a 16oz can of freon to check the system with, but before I could check the pressure, I had to jump out the AC relay to get the clutch to lock up. The pressure showed 0. I let loose with half the can, and the guage showed about 10lb, at which time I removed the jumper and put the relay back in. The AC clutch stayed engauged but would cycle on and off every couple of seconds. I emptyed the rest of the can and got the pressure back up to 26lbs with cold air out the vents and the clutch staying locked. I will check the pressure Tuesday to see if is holding pressure before getting another can of freon to get it up to the proper pressure.

I have a feeling that there was just enough freon in the system to keep everything working and get cool air but not enough to get cold air as the outside temp has not been very hot out, I also found out I was checking the switch on the high pressure side, and not the switch on the low pressure side. Now if only the system does not have a leak and holds pressure, I can top it off and life will be good again.

Thanks to all for the help I reveived as I now more about AC systems than I ever new, and the Ranger AC systems are not covered in the Hayens book, just a basic generic AC system, and not showing the pressure switches and locations