No A/C

[hackengineering]

I have an 06 i purchased and never been warm enough to know if the A/C was working. I noticed now that compressor clutch never has activated. I tested the high and low end pressure and both are very good. Traced the wires and so far no rub marks. No codes and A/C light just stays lit. Fuse is good. Tapped clutch and it is free but never activates. Anyone have suggestions.

 

[B.G. Smith]

If there is pressure in the system above about 44 lbs the compressor should come on when the fan is on and the switch on Rt. side of controls is pushed. If you can find the clutch cycling switch you can unplug and bypass it with a paper clip to see if that's the problem. It is on the low psessure side of system and used to be in the side of the accummulator. I looked at mine and it looks like there is something at the rear of the compressor which may be the new location of the switch. Also there have been some problems with the wire connection at the front of compressor. The fan speed resistor went out on mine and the AC would not work in the low fan position. You might try putting the fan in higher position and also try putting the control in the defrost position, I believe that may bypass the clutch cycling switch. bg

 

[hackengineering]

Thanks for all the advice BG, so far nothing has changed. I am wondering what other issue i may be having as i have never heard the engine fan clutch come on either and in know that is electrical clutch driven. I have never been close to overheating but i think that turns on when the A/C is on but not possitive. I did not try your jumper idea but i need to check to see if that is the accummulator behind the compressor. anyone know how to test the engine fan also. Are those two things even linked.

 

[LRutigliano]

I have an 06 i purchased and never been warm enough to know if the A/C was working. I noticed now that compressor clutch never has activated. I tested the high and low end pressure and both are very good. Traced the wires and so far no rub marks. No codes and A/C light just stays lit. Fuse is good. Tapped clutch and it is free but never activates. Anyone have suggestions.

How did you test the high and low pressures and determine they are "good" if the compressor is not engaging?



The most likely issue is that you have a refrigerant leak and are low.

 

[hackengineering]

Had a shop plug into both ends both were well above the factory pressure specs, (according to him) I am surprised the high end was in spec since the compressor was not on but i know the low end was because i was standing there and saw the gauge. Is the engine clutch and/or compressor 12v so i could possible jump each one and see if they at least work?

 

[B.G. Smith]

The AC clutch is 12volt as is the fan if it is electrically engaged. I have not been able to see the wires to the fan clutch on mine nor have I heard it engage much but truck runs fine/cool enough towing. Just be sure the wires are disconnected when you bypass them as you could mess something up in the controls otherwise. bg