Automotive Air Conditioning Information Forum (Archives)

Provided by

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

Compressor clutch running all the time, not cycling

joecimino on Wed July 23, 2008 1:27 PM User is offlineView users profile

Year: 1996
Model: TAHOE
Engine Size: 350
Refrigerant Type: 134A
Ambient Temp: 80
Pressure Low: 35
Pressure High: 198
Country of Origin: United States

I replaced the compressor/clutch on my Tahoe. At first the clutch was cycling nicely, but now it is just running all the time. The system is charged & air cold. I replaced the cycling switch on the accumulator bottle, but it still is not cycling. My dash board fan switch has now running at max when it should be turned off.

Please let me know of any suggestions you might have.

Thank you very much.


[email protected] or [email protected]

GM Tech on Wed July 23, 2008 2:53 PM User is offline

With 35 psi suction- you will not be cycling-- why is cycling so important to you? the system will cycle when demand is less (cooler out) and will never cycle when demand is high (as in high blower speed and high heat load- say 80 degreeF or more ambient). If you are trying to test to see if a system will cycle when needed to cycle- then unplug blower motor- and spray water on condenser, and keep hood open-- watch your suction pressure and note the off and on values. -- or just wait until it is cooler out....

The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.