Have a 03 durango that has a small leak in ac system somewhere , been to 3 shops and non can find it , so once every month or two I have add a can of freon and keep it cooling . Wife said it was not working and it needed a can . Got all set up and noticed ac clutch not engaging . Checked (swapped ) relay , good , tested voltage at compressor plug , also good . Just on a whim I put a jumper wire in relay slot from #30 pin to # 76 pin and clutch engaged so I started car and put in freon . Gage shows about 42-44 # running but when I pulled the jumper wire and reinserted relay , clutch stopped engaging and pressure went up to about 100# ( vehicle off ). I know this is a duel system and takes over 2 # but I think almost 1 # should allow clutch to work .Two questions , Does this 03 have a low pressure switch ( if so where , I have looked everywhere I can think ) and 2 Why do I have voltage at plug but clutch won`t work but I put in jumper wire and clutch works ? You guys have any thoughts ?

 

the relay should have power at 2 pins, one at all times, one in run and start. the 3rd pin is pcm grd control...the final is power feed to the clutch....you jumpered power to the clutch so it engages the clutch.
the A/C pressure transducer switch, which is mounted to a fitting on the line between the compressor and the condenser inlet. It has 3 wires going to it. 5 volt reference supply, signal and grd wires.

can filling is not accurate but 100psi static pressure should be enough to for the system to engage

 

Thanks Primem , yes the 30 pin was the hot and the 87 ( not 76 I wrote ) was to clutch . I never checked for which was hot in run / start position . But I did check plug at the clutch and it did show 13 v with the engine running , but the clutch wouldn`t engage . Since clutch worked with jumper wire I wonder why it wouldn`t while getting voltage to the plug ? I have looked all over for that pressure switch . I found what looks like it but it`s on high pressure side right next to radiator . As you can tell I`m not an ac mechanic , just a shade tree mechanic .
How could you check to other pin slot that is for PCM ground ?

Anyone else have any suggestions of any other things I could possibly check or test myself ? We are hoping to get her a new car at the end of the year and I was wanting to just keep it working for her until cooler weather gets here . Thanks for any replies .

 

dye is you best bet to find the leak

 

It has been to three shops , one was dealer and all used dye and/or something they called a " sniffer (?) " and all said they cannot find or detect a leak

 

Well if you're losing refrigerant you clearly have a leak somewhere. Take of the clutch and look at the compressor shaft seal.

 

sometimes dishsoap solutions sprayed onto the lines and components will locate the leak...works best on the high side due to access and the higher pressures when running. for the dye to work...you have to run the system for a week so it circulates. It can be hit and miss.

where is the rear evaporator for your model.

 

The dye works fine, you just have to over everything.

 

could also be leaking at the evaporator behind the dash, cant locate a leak with dye if you cant see where the leak is coming from . . .

 

Hi did you get your AC figured out yet ? I am having the same issue with my 2004 durango .i have a ground loose some where in that ac system . 2004 wiring diagram are really hard to find . Do you have one by chance on AC . I have one for alot of 04 durango but not the AC wiring . Thanks