Stock A/C compressor without the PCM
Stock A/C compressor without the PCM Tried a search and no luck. I have a 2001 truck compressor on my 6.0L. Is it possable to use without it being controlled by the pcm? If so, is there a special way to wire it up? When I put 12v to the plug on the compressor, I see the clutch move but then it starts to smoke and sizzle. Not good! Thanks.
Tried a search and no luck. I have a 2001 truck compressor on my 6.0L. Is it possable to use without it being controlled by the pcm? If so, is there a special way to wire it up? When I put 12v to the plug on the compressor, I see the clutch move but then it starts to smoke and sizzle. Not good! Thanks.
I have a seperate pressure switch so that's not a problem. When I looked up info on running it with the PCM, it sounds like the PCM sends 12v to turn it on, correct? So far, that 12v just gives me smoke, so is there something I'm missing?
I didn't use the PCM to control my 71 Chevelle AC.. I just wired the Compressor clutch switch to the 71 Chevelle controller and it has been working for the past year and a half without any problem... everything is stock OEM Chevelle except the Compressor.
12v to compressor through a relay will work. The PCM sends the signal through a relay as well. So, the relay may already be there. Just mount a switch inside the car to control the relay & that way you will have on command AC. If the compressor is smoking, then the clutch is slipping, if you mean that it smokes while the belt is turning. If it's just plain smoking without turning, then I'd say it's a bad compressor. Either way it should be replaced.
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Joined: May 2004
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From: SoCal
I have a question on a '01 Fbody harness: I notice that the harness wires to the connector controlling the compressor clutch appear to be a very small gauge. Does the PCM directly control the clutch through these wires/connector? How would the relay be part of how it operates?
Thanks,
Andy1
Thanks,
Andy1
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The PCM doesn't do anything magical in how it "controls" the compressor. It acts as a binary switch (high and low cutouts for the highside), WOT switch, RPM switch, and idle kickup solenoid. Any clutch cycling for temperature/freezeup control needs to be done independant of the PCM--I'm planning to feed the clutch control output of the VA-GEN-IV controller (handles on/off and temp-based clutch cycling) to the AC request signal on my LS1 PCM. Right now I've got the VA controller running the compressor directly through a binary switch on the drier, but I'd really like to get WOT switch and RPM switch functionality of the PCM. I'll keep the binary switch between the PCM's AC relay and the compressor when I do finally put the PCM into the mix. I have the PCM already controlling the fans for AC--all you have to do is hook up the AC Refrigerant Pressure Sensor and the fans start working for the AC, don't even need AC Request hooked up. When I was testing the AC was the first time I've ever heard my fans kick into high speed mode 
(other than a manual test with HPTuners).
(other than a manual test with HPTuners). TECH Resident
Joined: May 2004
Posts: 792
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From: SoCal
I have a question on a '01 Fbody harness: I notice that the harness wires to the connector controlling the compressor clutch appear to be a very small gauge. Does the PCM directly control the clutch through these wires/connector? How would the relay be part of how it operates?
Thanks,
Andy1
Thanks,
Andy1
Andy1
Ok, tried another compressor off an 03' 5.3L. Same result. Within 1 second of giving it power, it starts to smoke. Not the belt, but the compressor itself. So I don't think it's the compressor now. Those of you not using the PCM, did you swap to another clutch system or something? What is your compressor off of ? I was told today by an ex GM tech that he thinks my compressor is pulse width modulated and will have to be run by the PCM, but wasn't 100% sure. Were not all LSx compressors this way? Thanks again.
On my 71 Chevelle... which I used today and blew below 50 Deg using the R406A Refrigerant replacement.
1) Used 71 Chevelle wiring and controls
2) Green Wire from the original Chevelle AC system to the Green Wire on the LS1 clutch connector (I think, its been a while and it is all wrapped up now. but you might check the wiring for a 99 Camaro).
3) Grounded the other termnial
4) Stock 99 F-Body/Camaro Compressor
5) All of the HAVC box and controls are all 71 Chevelle, Hose were modified by the local tubing shop to mate up with the LS1 compressor and the 71 Chevelle system. Bottom line is that the AC system is stock 71 Chevelle with the LS1 compressor swap in place of the original 71 Chevell Compressor.
I am not sure if there is a problem as some of the experts might want to tell me or warn me... but all I can say.. it works (for now ?? LOL).
1) Used 71 Chevelle wiring and controls
2) Green Wire from the original Chevelle AC system to the Green Wire on the LS1 clutch connector (I think, its been a while and it is all wrapped up now. but you might check the wiring for a 99 Camaro).
3) Grounded the other termnial
4) Stock 99 F-Body/Camaro Compressor
5) All of the HAVC box and controls are all 71 Chevelle, Hose were modified by the local tubing shop to mate up with the LS1 compressor and the 71 Chevelle system. Bottom line is that the AC system is stock 71 Chevelle with the LS1 compressor swap in place of the original 71 Chevell Compressor.
I am not sure if there is a problem as some of the experts might want to tell me or warn me... but all I can say.. it works (for now ?? LOL).
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From: Texas
I am about to do this on my swap. Can you guys tell me which line on the LS1 compressor routes to the condensor and which one routes to the evaporater? Refer to diagram.
Also Bczee you mentioned you're using the R406A Refrigerant. Is that equivialnt to the r12 systems. I thought 134A was the new stuff used today. Reason I'm asking because Hotrod air said no problem using the Ls1 compressor but that I should replace my factory condensor to a 134A unit to improve performance. I am fimilar with freeze 12 being used in R12 systems. What is the scoop on R406A Refrigerant? Is it better in the older systems than 134A? Thanks in advance
Also Bczee you mentioned you're using the R406A Refrigerant. Is that equivialnt to the r12 systems. I thought 134A was the new stuff used today. Reason I'm asking because Hotrod air said no problem using the Ls1 compressor but that I should replace my factory condensor to a 134A unit to improve performance. I am fimilar with freeze 12 being used in R12 systems. What is the scoop on R406A Refrigerant? Is it better in the older systems than 134A? Thanks in advance
If my 99 compressor and manifold are the sames as your 02', Then Port/tube A is your low pressure side with the larger of the hose/tubes and goes to your HAVC box. The Port/Tube B s your high pressure side and goes to your front condensor. (in general..the larger tube will usually be the low pressure or the return side and the smaller tube will be the high pressure side of a system... your Power steering and heater hose are the same)
I don't know too much about the R406A.. as I got it at the Good Guys show. Some vendor was pushing it as a R12 replacement and that you wouldn't have to flush and replace all of your O-Ring (I did anyway). The R134A PAC oil is what will degrade the older O-Rings and seals. And that the properties are closer to R12 than R134A.
I though I had saved one of the cans but I can't find it or the web site that they have.. They may be up at Reno this coming week for Hot August Nights. If they are, I will get the info again else I will keep looking for the info.
I am not the expert on all of this, I just know enough of the basic, I am sure someone will ping in and tell us more about the properties of the Refigerant and that I should do something or it shouldn't work.. but for now.. it is working ok. If it blows up.. then I'll go to some other plan B... LOL..
Good luck
I don't know too much about the R406A.. as I got it at the Good Guys show. Some vendor was pushing it as a R12 replacement and that you wouldn't have to flush and replace all of your O-Ring (I did anyway). The R134A PAC oil is what will degrade the older O-Rings and seals. And that the properties are closer to R12 than R134A.
I though I had saved one of the cans but I can't find it or the web site that they have.. They may be up at Reno this coming week for Hot August Nights. If they are, I will get the info again else I will keep looking for the info.
I am not the expert on all of this, I just know enough of the basic, I am sure someone will ping in and tell us more about the properties of the Refigerant and that I should do something or it shouldn't work.. but for now.. it is working ok. If it blows up.. then I'll go to some other plan B... LOL..
Good luck
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From: SoCal
Line B would be the pressure side and goes directly to the condensor, a #8 hose. That's how I did mine. Doc's Blocks makes compressor blocks for the Fbody one with fittings that point in various directions to suit your needs.
Andy1
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From: Texas
quote" Doc's Blocks makes compressor blocks for the Fbody one with fittings that point in various directions to suit your needs. "
I still have the factory F-body block with hardlines on it. I cut the hose off of it and bent it slightly appears to fit my A body ok. Classic Air here in Fort worth said they could weld on screw on fittings to the hard lines and make new hoses. I'm going to try that. If that turns out to not be the case I'll check out doc's blocks. What ever is used has to be close to the original Fbody block to clear my cross member. I got maybe 1.5 inches to the back of the compressor. Thanks for the info guys and keep me posted on the R406A. Sounds like the way to go in my original factory setup.
I still have the factory F-body block with hardlines on it. I cut the hose off of it and bent it slightly appears to fit my A body ok. Classic Air here in Fort worth said they could weld on screw on fittings to the hard lines and make new hoses. I'm going to try that. If that turns out to not be the case I'll check out doc's blocks. What ever is used has to be close to the original Fbody block to clear my cross member. I got maybe 1.5 inches to the back of the compressor. Thanks for the info guys and keep me posted on the R406A. Sounds like the way to go in my original factory setup.
