I can get the AC to operate if I jump the clutch relay - AC Clutch engages and I get cool air. The wiring diagram shows the AC clutch is grounded through the PCM. I notice the radiator cooling fan does not turn on when the AC system is turned on. Can the cooling fan be bad and the root cause of AC system not running? I've replaced the AC pressure transducer - no luck.
04 LS V8 AC will not operate
- Thread starter adiachun
- Start date
joegr
Dedicated LVC Member
Most likely, your pressures are wrong and you are just going to make things worse not knowing what you are doing. Take it somewhere that they will put high and low pressure gauges on it and see what is going on. If it is low on refrigerant, you'll need to have the leak fixed. The fan won't turn on for the AC if the pressure is too low, or if the compressor is not pumping correctly. Without seeing both the high and the low side pressures, you won't know what is going on and adding refrigerant may cause more harm than good.
Thanks, but if I wanted take it somewhere I would not have bothered to post. Ive gotten some useful advice from the posts here in the past. I was hoping for more. I've already checked pressure which is ok. it runs cold by just jumping the relay. id think that the root case must be on the ground side of the relay, which, as I said appears to be the pcm.
A/C is one of the things best left to the professional with the proper training, experience and tools. The system has multiple opportunities to ruin your day.
1LoudLS
Dedicated LVC Member
both the high and the low?
Fyi, too close this out. My local professional mechanic I use when I get stuck spent several hours on this and thought it might either be pcm or a wiring. He finally found and fixed wiring issue. Car had some front end damage before I got her. 3rd wiring problem that had to be fixed. Awesome ride when she's in a good mood.
1LoudLS
Dedicated LVC Member
all very important information that would have been needed to know before any helpful advice could have been given in your case.
normally, wiring issues are one of the last things you would suspect as the problem unless a car was flooded or wrecked, then it moves right up to the some of the top things on that list.
at least you got it figured out!