A/C stopped out of the blue

I attempted to use my 1998's voyager A/C for the first time this year and the compressors clutch isnt kicking in...I purchased one of those new r-134 gauges and it said its something other than low refrigerant....I use to do mechanics 15-20 years ago and we were able to jump the compressor back then to see if its operable..Does anyone know if there is a way to jump the compressor or are there any electrical swithes that may cause the compressor/clutch to shut down..There was never any noise or signs of the clutch blowing so I have a feeling its electrical..I also unplugged the connection at the compressor and did a line test on the two wires and neither was sending any current with the A/C on...Any help would be appreciated..Thanks All!!!!!

Your A/C pressure transducer, which is normally mounted the H-block on your firewall, has an electrical connector, that's the pressure transducer. If that's bad, it'll cause the clutch to not engage.

Ok..Thanks much...Would you know if there is a way to bypass the transducer to see if thats the problem? Hate to get knocked over the head at a mechanic for a switch I can replace..I know they will tell me its something bigger for the $$..Thanks again...

Chances are you are low on freon. But since you have been out of this for a while. The pressure readings are not the same as they were for r12 so be careful.

I thought that but I tried to add it w/ one of those new cans out there w/ the gauge attached and it said that the level is fine but then again, I dont think it will take freon in unless the clutch is on, that why I am trying to jump the clutch..Thanks

Yes you will have to get compressor up and running to fill completely. But you should be able to get enough so switch will engauge clutch. You can always put the can into hot water to increase pressure in can.

Ok..Thanks much...Would you know if there is a way to bypass the transducer to see if thats the problem? Hate to get knocked over the head at a mechanic for a switch I can replace..I know they will tell me its something bigger for the $$..Thanks again...

Best way to get your compressor going is jump the terminal connector with a paper clip, if it runs, then you are undercharged and it'll go from there. If when you charge it up and it still doesn't work, your pressure transducer is faulty.

Does the whole system need to be purged to replace the transducer or is it replaced without losing the 134a?? Thanks

the system doesn't need to be discharged to change the transducer, it's a simple fix you can do in your driveway.

the system doesn't need to be discharged to change the transducer, it's a simple fix you can do in your driveway.
I appreciate all your help..You said that I can jump the transducer with a paperclip..Only problem is there are three wires going to the transducer....I tested one of them and it was hot but I didnt know which other one to jump and I dont want to jump the wrong one and screw up the computer..Any idea which one gets jumped? I also tested to see if the other two became live when the a/c was on and they didnt so I am guessing the transducer is shot..