A/C, cooling fans and compressor not working

1994 CADILLAC FLEETWOOD
85,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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SNAKEBITN
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Here is what i have: A/C compressor, cooling fans hi and low speed inoperable. Pulled vacuum, compressor turned on for half can, then quit, fans never came on. I have no power to the fans. all fuses are good. replaced compressor relay. found a broken wire. Still no A/C?
Aug 12, 2019 at 1:28 PM
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ASEMASTER6371
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Good afternoon,

What wire was broken?

1/2 can is not enough. You need to add as much as it will take. Remove the negative battery cable and reinstall and then try the A/C system again.

Roy
Aug 12, 2019 at 5:34 PM
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SNAKEBITN
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The wire was the A/C compressor relay in the under hood fuse box with the 2 /40 amp fuses,they are good. I replaced the relay with AC Delco one. I was closing up the shop moving the car around I heard the A/C compressor kick on. I put the rest of the can in and the compressor quit again.Cooling fans never came on. The orifice had a lot of gunk on it so I replaced it earlier in the day.
Aug 12, 2019 at 6:15 PM
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ASEMASTER6371
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Once the compressor stays engaged the high side pressure builds, the AC fan should come on. It sounds like you do not have enough freon in the system. Thats why it is shutting off.

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Can you give me the high and low side readings of the system?

Roy
Aug 13, 2019 at 2:38 AM
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SNAKEBITN
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Static pressure reading is 100 on both sides. When the compressor did come it dropped to 35 took the half can. The compressor cycled then pegged out the low side 300 psi. I am thinking compressor is gone out.
Aug 13, 2019 at 5:02 AM
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ASEMASTER6371
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Okay, yes, if the low side spiked to 100, then yes, it sounds like you have something going on.

I would replace the compressor, dryer, expansion valve and make sure the condenser is clear.

Roy
Aug 13, 2019 at 6:41 AM
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SNAKEBITN
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Hey, I did all that yesterday charged the system took quite awhile. Still no cooling fans coming on. Low side kept building too much Psi cause no fans coming on. Another suggestions replacement of the fans next.
Aug 16, 2019 at 5:48 AM
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ASEMASTER6371
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Did you clear out the condenser? With 100 lbs. on the low side, you have a blockage somewhere.

Roy
Aug 16, 2019 at 1:46 PM