Well, I got my first diesel 5 days ago and I knew it had problems with the A/C before I bought it and now it's getting to me, especially mid day when having the windows down doesn't cut it. But to start off, I can turn my dials to max ac or to defrost and it does absolutely nothing at all. So I checked et vacuum pump and it doesn't even come on when I discharge the vacuum tank which should make it cut on immediately. And the only air I get comes out of the defrost while I'm on the highway and even then it barely comes out. But heat comes out when I switch it to heat and slightly cool air comes out when I switch it to cold. I need this problem fixed soon and I don't want to take it somewhere because I jus spent all my money on this truck. Thanks for your time and hopefully we can get this resolved

-Hunter

 

The vacuum pump should have voltage at all times when there is no vacuum built up. Check to see if you have voltage to the connector - it may be as simple as a fuse.

 

Ya Rich, thats one of those fuses you can steal and put in somewere else, till I get some more fuses.Passenger fuse #28 on my 99

 

'99 and '01 have the same wiring - the OP has an '01. There was a dramatic change in '02, so I'd have to look up the fuse number if that was the case.

 

I'm finally done with all my college classes for the day so now I can finally get out there to start diagnosing the problem. And thanks for the replies

 

Okay, #28 was fine but under the hood in the fuse box #16 is missing and the fuse panel up under my dash has a bunch of missing numbers: 2,5,6,9,10,17,21,25,26. And I found a couple vacuum lines that were disconnected from dry rot but the pump should still be coming on. And why isn't my defrost/vents coming on at all? Even without vacuum it should come out of the defrost vents right?

 

Not sure if you have an electrical problem or if the system is low or completely out of refrigerant. Based on your other post, I am under the impression you are low on refrigerant. It was working as you drove but air became warmer and it quit working.

With the hood open engine at idle and a/c on, is the compressor clutch engaged and the compressor turning? If Yes- Are you low on refrigerant and the compressor is short cycling? If No, can you add refrigerant and get the compressor to kick in?

I would hit the auto parts store and get one of there a/c charge kits that has the gauge built in to the can top. The instruction are well written and easy to follow.

 

No, it doesn't blow anything at all. Turning the **** in the truck for the air (for the a/c) to full is the same as having the air completely off. It doesn't even try to work. And why would the compressor not blow any air at all? Like the electric fan that blows the air doesn't even come on to move the air through the vents

 

It sounds like you have multiple problems. #1, does the fan blow when the heat is on? I'd start with the HVAC fan and get it working if it was my truck. JMO.

 

I'm trying to get it working.... And no, no fan engages and no air comes out at all. The switches due absolutely nothing in the truck

 

The blower is right over the heater core, on the passenger side. My blower crapped out not long ago, so it's not a strain to assume yours could be out as well. Check the power to the blower before you make a move. I don't have my paper wiring diagrams with me right now, so I can't look up those fuses until later.

 

If your heat/AC switch (the one on the right) is not working or getting power nothing else will work at all. It has to come off of "off" first. So...if it is not getting power or passing it on (i e it's broken or worn out) you will get nada. finding the blower and putting power directly to that will help guide you in the direction you need to go. But then the vacuum pump is a different thing. It should be getting power any time the key is on.

 

How do I put power directly to the blower?

 

My ways of doing things are ummm different than others but I would take power directly from the battery, which is pretty close and run power and ground to the connections for the blower. Tugly has explained where the blower is located. I do not know where the connector block is I would have to find it.

 

Yeah I know where the blower is. I'll test it later and let you know how it goes