2001 Oldsmobile Aurora A/C Compressor Won't Engage

Problem with my 2001 Oldsmobile Aurora 3.5 v6. Has new engine, cooling system, transmission (all from dealer under warranty. Question: My air conditioning system does not work. The the HVAC controls light up but the compressor does not engage. I checked all the fuses that I could find that are related to the HVAC system and they are all fine. Also under the front driver side carpeting, it is soaked with water. I don't know if this problem is related or not, but I thought maybe it could be a leak related to the evaporator.

I checked the R134 level and that seems fine. What i would like to know is first of all where I would be able to find the evaporator if you think that might be the issue(or at least part of it. Also what else should i be looking for to Diagnose and repair the problem. Could it be a relay and if so, how can I check to make sure it/they are working correctly? Keep in mind the compressor pulley is rolling it's just not engaging the system. I can't find any leaks anywhere else underneath the car or any funky odors. Thanks in advance for your help.

oldsmobile aurora


Did this A/C problem occur right after all the work to engine, etc. was done? If so, i would suggest calling the dealer and tell them that the A/C does not work since repairs were made. They should check it out for you for free. The mechanic may have just left something unplugged, or possibly pinched a harness. If they are a good delaership they will take care of you if it was their fault.

If not, then i can get you a schematic to use with a test light and volt / ohm meter to assist in diagnosis. First, The A/C CLU fuse and the A/C CLU relay in the underhood fuse block are the first things to check. An easy way to check a relay is to swap it with another of same type and number of terminals with another in that fuse block.

There is also a pressure switch on the back of the compressor- Make sure that is plugged in. Also a pressure sensor on the line off the back of the compressor- make sure it is plugged in. The Powertrain computer (PCM) controls the relay to engage the clutch when it is requested. I will send out a schematic if you would like.

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