A/C Recharge Procedure on Venture

Wondering if someone can point me in the right direction. I have a 1999 Venture - recently purchased - AC doesn't work. I suspect a leak somewhere - (compressor shaft seal, or maybe the condenser). I'm not sure that condensor problem applies to the ventures up through 2000 or not, but either way, if it's a leak I need to recharge to find it. To do so, I got the guage/filler nozel with the R134a refrigerant.

Presently - the compressor is not kicking on when the AC button is pushed. I suspect this is because the safety mechanism that stops the compressor when coolant/oil is low has activated.

Further I (assume) that the compressor must engage to pull the refrigerant out of the canister? The canister doesn't appear to be under pressure - or I could be missing something. So question: If the compressor isn't kicking on - and the reason is that the refrigerant is low, can I still use the do-it-yourself procedure or do I need to take it to have A/C specialists hook it up to a machine to fill?

I suppose it is wise to first check for electrical issues, or make sure the compressor hasn't blown out before I attempt filling it anyway. So another question: is there a proper procedure to bypass the safety mechanism, and hook up the compressor to the battery to test if it engages at all?

Any suggestions (or links to other threads) appreciated.

Sorry- you have been mis-informed- there is NO low side pressure cycling switch on a Variable stroke compressor system such as yours...it has a high side 3-wire pressure transducer, that cannot be jumpered....your can pressure will drive up the system pressure enough to energize the compressor- once system pressure hits 47 psi.

Variable compressors use the compressor displacement to avoid system freeze-up, they do not shut off for freeze protection as the old fixed displacement compressors. Anyone with a U-van should know this-- since they never hear the compressor cycle when the a/c is running as normal.

Also the condenser leak problem was ONLY in '01 and '02 U-vans and Azteks and Rendezvous-when those system went from Delphi (2000 and prior MYs) to the Mitsubishi compressor and entire system- so it is a manufacturer problem- Mitsubishi that cause the condenser snafu.

I'd look at the compressor shaft seal and belly o-rings on you're model year vehicle..

OK - thanks for the info. I will proceed then with adding the coolant and go from there.

if the shaft seal is leaking the dealer has a kit i think i gave $45.00 for it and its been working for 4 years. be easy on the bolt that hold the hoses to the compressor as it will strip out easy