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99 deville ac high pressure side through the roof

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I just replaced the compressor and accumulatoer and orifice tube on my 99 deville. when I charged the system the compressor will not engage. the fuse is good but not getting power to the pressure switch. Also the high pressure side goes past 450 when i jump the compressor to make it run.

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It's normal for the high side pressure to go up when the compressor runs, particularly if the system is hot, i.e. when it is first turned on. The trick is, how fast does the pressure go so high? The system, when operating properly, will cycle the compressor to keep the high side pressure under control

Did you pump down the system before refilling it? Is it possible that the system is overfilled?

If the compressor clutch is not getting power, either you need to reset a code as Göran W says, or something is causing the system to throw a code quickly. If you are resetting the codes and still can't get the compressor to come on, read out the codes and post them here.

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Did you pull a deep vacuum on the system for 45 minutes minimum before charging the system? If not, you have moisture in the system which will increase high side pressure.

Did you charge 2.0 lbs. of refrigerant in to the system?

'93 Fleetwood Brougham
'05 Deville
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