AIRCONDITIONING SYSTEM PROBLEM
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From: RIGBY IDAHO
AIRCONDITIONING SYSTEM PROBLEM
I CANT SEEM TO GET MY AIRCONDITIONER TO TURN ON IS THERE A WAY TO TROUBLE SHOOT THE SYSTEM? I CHECKED THE FUSE AND THERE IS POWER TO BOTH SIDES BUT WHEN I CHECK THE PLUG ON THE PUMP THERE IS NO POWER. MY CHILTONS GIVES ME NO INFO ON THIS CAN SOMEONE HELP ME?? :confused:
[Modified by VETTEMANIAC, 4:09 AM 5/12/2004]
[Modified by VETTEMANIAC, 4:09 AM 5/12/2004]
Pro
Joined: Jun 2003
Posts: 559
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From: OKC OK
Re: AIRCONDITIONING SYSTEM PROBLEM (VETTEMANIAC)
SunCR is the MAN when it comes to Vette A/C issues!
For my $.02...you can unplug the low pressure switch from the larger line near the firewall and jumper it with a paper clip to get the compressor to run while you add R12/134a.
I suggest taking the hit and buy yourself a good set of manifold guages. I have found them to be indespensible when working on my Vette's A/C. As a matter of fact I checked my A/C this afternoon and only had to add about a pound to bring her up to speed for this summer. I'm thinking a Targa shade and darker tint wouldn't be a bad idea either. :seeya
For my $.02...you can unplug the low pressure switch from the larger line near the firewall and jumper it with a paper clip to get the compressor to run while you add R12/134a.
I suggest taking the hit and buy yourself a good set of manifold guages. I have found them to be indespensible when working on my Vette's A/C. As a matter of fact I checked my A/C this afternoon and only had to add about a pound to bring her up to speed for this summer. I'm thinking a Targa shade and darker tint wouldn't be a bad idea either. :seeya
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Instructor
Joined: Apr 2002
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From: RIGBY IDAHO
Re: AIRCONDITIONING SYSTEM PROBLEM (MtlSphere)
SO IF I HAVE A LOW FREON CONDITION WHEN I ACTIVATE THE AIR SWITCH THE COMPRESSOR CLUTCH WILL NOT ENGAGE AND THE COOLING FAN WILL NOT COME ON EITHER ? THIS PROBLEM SEEMS TO APPEARED AFTER I TOOK HER OUT OF STORAGE ITS A 1985 IF THAT MAKES ANY DIFF. ALSO WILL I BE ABLE TO RECHARGE THE SYSTEM WITH A 134 KIT?DO I HAVE TO RESET ANYTHING ON IT AFTERWORDS??
[Modified by VETTEMANIAC, 5:24 AM 5/12/2004]
[Modified by VETTEMANIAC, 5:24 AM 5/12/2004]
Le Mans Master
Joined: Dec 2000
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From: San Diego, Ca
Re: AIRCONDITIONING SYSTEM PROBLEM (VETTEMANIAC)
As suggested, disconnect the low pressure switch and jumper the harness with a paper clip. If it runs, the charge is probably low.
I'm not a fan of dumping in R134 via one of the quickie conversion kits. You need to get all of the R12 out first. Mixing the 2 refrigerents will increase operating pressures, sometimes high enough to trip the high pressure switch (and if it doesn't, it's just going to blow up). So, if you want to use R134, get all the old stuff out first, swap out the accumulator and orifice, pull a vacuum, and then recharge using ester (not pag oil) for the lubricant.
I'm not a fan of dumping in R134 via one of the quickie conversion kits. You need to get all of the R12 out first. Mixing the 2 refrigerents will increase operating pressures, sometimes high enough to trip the high pressure switch (and if it doesn't, it's just going to blow up). So, if you want to use R134, get all the old stuff out first, swap out the accumulator and orifice, pull a vacuum, and then recharge using ester (not pag oil) for the lubricant.
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Instructor
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From: RIGBY IDAHO
Re: AIRCONDITIONING SYSTEM PROBLEM (SunCr)
Thanks for the info guys it is working great the only problem I have now is that I cant get the fans in front of the radiator to work when I turn on the AC and the one behind the radiator cycles on and off. I disconected the battery to reset the pcm and it still doesnt work. Is there a sensor that im not aware of??
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Le Mans Master
Joined: Dec 2000
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From: San Diego, Ca
Re: AIRCONDITIONING SYSTEM PROBLEM (VETTEMANIAC)
Aux fan in front of the radiator is independent of a/c operation. On your year, I believe the switch for it is in the right head between the 6 & 8 plug. It will close and ground the relay when coolant temps reach 228 degrees. Grounding the wire should turn on the fan.
Pro
Joined: Sep 2003
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From: charlotte nc
Re: AIRCONDITIONING SYSTEM PROBLEM (SunCr)
As suggested, disconnect the low pressure switch and jumper the harness with a paper clip. If it runs, the charge is probably low.
I'm not a fan of dumping in R134 via one of the quickie conversion kits. You need to get all of the R12 out first. Mixing the 2 refrigerents will increase operating pressures, sometimes high enough to trip the high pressure switch (and if it doesn't, it's just going to blow up). So, if you want to use R134, get all the old stuff out first, swap out the accumulator and orifice, pull a vacuum, and then recharge using ester (not pag oil) for the lubricant.
I'm not a fan of dumping in R134 via one of the quickie conversion kits. You need to get all of the R12 out first. Mixing the 2 refrigerents will increase operating pressures, sometimes high enough to trip the high pressure switch (and if it doesn't, it's just going to blow up). So, if you want to use R134, get all the old stuff out first, swap out the accumulator and orifice, pull a vacuum, and then recharge using ester (not pag oil) for the lubricant.
SunCR is right on target. If you convert to R134A , do it the right way or you will be replacing more than the freon. :cheers:
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Instructor
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From: RIGBY IDAHO
Re: AIRCONDITIONING SYSTEM PROBLEM (VETTEMANIAC)
THE AC WORKS GREAT NOW THE ONLY QUESTION I HAVE IS THE COOLING FAN CYCLES ON AND OFF NOW IS IT NOS SUPPOSSED TO RUN ALL THE TIME THE AC IS ON? AND IF SO HOW DO I CORRECT THIS ? T.I.A.
Le Mans Master
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From: San Diego, Ca
Re: AIRCONDITIONING SYSTEM PROBLEM (VETTEMANIAC)
It's suppose to cycle on and off. Most of the early C4's use a dedicated switch on the high pressure (smaller line from the condensor to the evaporator) that will open at about 233 psi signalling the ECM to ground the main fan relay. The cooler air flow across the condensor drops the pressure and when it it gets to about 170 psi, the switch closes and ECM shuts the fan off. The idea is to keep the low side at 22 to 28 psi which gives the best vent temps. Later C4's incorporate the signal into a pressure switch which the ECM uses to control both fans, fan speed and to monitor the status of the a/c system all of which can be read by a scanner. The idea is the same though - keep the operating pressures within the ideal operating range.
[Modified by SunCr, 4:59 PM 5/16/2004]
[Modified by SunCr, 4:59 PM 5/16/2004]