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2003, 3.8l with air conditioning problems

  • Thread starter Thread starter Jimb0z '03
  • Start date Start date Nov 3, 2024
J

Jimb0z '03

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Nov 3, 2024
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Kissimmee, Florida
Nov 3, 2024
#1
  • Nov 3, 2024
  • #1
Hi yall. I am having an issue with the air conditioning in my 2003. Its got a 3.8 liter in it. I was driving using the ac about a month ago. It was working fine, blowing out cold. I shut the car off and did what i had to do, and when i started the car up again, the ac had quit working. So i checked out all of the fuses, and they were all good. I started checking things out. The system had a full charge of freon. There was power at the high pressure switch, and power at the low pressure switch. The only place there wasnt power was at the ac compressor. I researched and found out about the relay module underneath the passenger side fender, so i replaced it with a second hand module i bought here off market place. Still, no power at the ac compressor. I started checking out the compressor and the clutch seemed awful loose, and the compressor itself seemed locked up. So, i spent a ton of money and bought a brand new compressor, (not rebuilt), a new condenser, new receiver dryer, orifice tube, low pressure hose, and high pressure hose and manifold assembly as well. After installing everything, i still have an ac system that has no power to the compressor. I tried jumpering the high and low pressure switches, and that does nothing at all to change the issue. Then i thought that the ccrm that i put in may have been the issue since it was second hand. So i went out and bought a new one of them and put it on as well. Much to no avail. It didnt change a thing. I am absolutely stumped. What could possibly be left that i am overlooking? Do any of yall have any experience in this area that can possibly shed a little light on my problem?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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#2
  • Nov 3, 2024
  • #2
Go back to the relay location and test for power.

Test for power at each of the pressure switch locations as well.

Place a jumper at each of these locations if/when you find 12 volts as you travel down the path.

Check the A/C switch itself for power and ground and finally, the connector to the A/C clutch.


Question: Have you had the system sucked down and charged to specification since changing all of those parts?
 
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Jimb0z '03

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Nov 3, 2024
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Kissimmee, Florida
Nov 3, 2024
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  • Nov 3, 2024
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Yeah. We did that today. The system vacuumed down real well. It stayed down as well. There was zero leak down. Since the compressor wouldnt come on, it wouldnt take a full charge. It took a 12 ounce can and a half, but the compressor still never kicked on. So when that happened, i did check the power at the pressure switches and there was power at both. Then i tried jumping them off. I jumped first the high side, then the low side, then both, but still no power at the compressor. I thought it may have been one of the pressure switches but no. This is the third ccrm. And its new. Can i ask you, if the switch in the dash were bad, would there still be power at the pressure switches? My guess would be no. So i doubt that it's the switch on the dash. Could it be the temperature switch on the dash? How does it work? Could that be the problem?
 
J

Jimb0z '03

New Member
Nov 3, 2024
7
0
1
Kissimmee, Florida
Nov 3, 2024
#4
  • Nov 3, 2024
  • #4
Noobz347 said:
Go back to the relay location and test for power.

Test for power at each of the pressure switch locations as well.

Place a jumper at each of these locations if/when you find 12 volts as you travel down the path.

Check the A/C switch itself for power and ground and finally, the connector to the A/C clutch.


Question: Have you had the system sucked down and charged to specification since changing all of those parts?
Click to expand...
Yeah. We did that today. The system vacuumed down real well. It stayed down as well. There was zero leak down. Since the compressor wouldnt come on, it wouldnt take a full charge. It took a 12 ounce can and a half, but the compressor still never kicked on. So when that happened, i did check the power at the pressure switches and there was power at both. Then i tried jumping them off. I jumped first the high side, then the low side, then both, but still no power at the compressor. I thought it may have been one of the pressure switches but no. This is the third ccrm. And its new. Can i ask you, if the switch in the dash were bad, would there still be power at the pressure switches? My guess would be no. So i doubt that it's the switch on the dash. Could it be the temperature switch on the dash? How does it work? Could that be the problem?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
42,933
21,110
234
Box behind Walmart
Nov 3, 2024
#5
  • Nov 3, 2024
  • #5
Jimb0z '03 said:
Can i ask you, if the switch in the dash were bad, would there still be power at the pressure switches?
Click to expand...

I would have to look at a diagram to be sure but in general: The entire system is energized and the switch completes the circuit to ground. So if the wiring is good and you power at the relay and both pressure switches then you should have power at one of the wires at the switch.

If not, then the wiring issue is in-between.
 
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Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
42,933
21,110
234
Box behind Walmart
Nov 3, 2024
#6
  • Nov 3, 2024
  • #6
Oh, and I also wish I had a nickel for every bad-out-of-the-box CCRM threads I've seen around here.

Cannot vouch for them at all.
 
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Jimb0z '03

New Member
Nov 3, 2024
7
0
1
Kissimmee, Florida
Nov 4, 2024
#7
  • Nov 4, 2024
  • #7
Noobz347 said:
I would have to look at a diagram to be sure but in general: The entire system is energized and the switch completes the circuit to ground. So if the wiring is good and you power at the relay and both pressure switches then you should have power at one of the wires at the switch.

If not, then the wiring issue is in-between.
Click to expand...
Thank you for
Noobz347 said:
Oh, and I also wish I had a nickel for every bad-out-of-the-box CCRM threads I've seen around here.

Cannot vouch for them at all.
Click to expand...
Its either that or the switch
 
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