Air conditioner problems

1999 CHEVROLET EXPRESS
240,000 MILES • 5.0L • V8 • 2WD • AUTOMATIC
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CARLSHONDAS85
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  • 2 POSTS
The air conditioner compressor is not getting power, i used a power probe to apply power to compressor and the compressor kicks on and blows cold air, i then went to the relay and was able to jump terminal 87 to 30 with power probe and once again the compressor kicks on and blows ice cold, not sure where to go next.
Jun 14, 2016 at 5:04 PM
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MHPAUTOS
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  • 31,937 POSTS
System pressures may be low enough to activate the low pressure switch which will shut down the compressor, get the refrigerant high and low pressures checked first post the readings here for further assistance.
Jun 15, 2016 at 1:42 AM
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CARLSHONDAS85
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Ok at 80°F the low was around 39psi and the high was 187psi
Jun 15, 2016 at 2:34 AM
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STRAILER
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  • 53,854 POSTS
Hello,

Check all fuses, and the pressure switches, here is a wiring diagram to help you check things out

let me know what you find

Best, Ken

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Jun 17, 2016 at 8:40 AM