Buick Repair Questions? Ask a Mechanic for Answers ASAP
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Do you haVe a set of manifold gauges so we can check the operating pressures of the system both high and low side
That is our next step. We need to confirm that the pressure is there to close the switch for fan operation.
so you dont have any gauges. Okay well lets assume the pressure is there and the fan is being requested. Let me pull up the wiring
the high pressure sensor is in the line behind the ac compressor check and make sure it is plugged up
That sensor is what the ecm uses as an input to turn the cooling fans on for the ac system. Once head pressure climbs in the high side it turns fans on perhaps it got pulled loose or left off from a previous repair
That switch doesnt close until 225 psi I beleive if you are not getting above 150 it want cut on.
You said you could disconnect the temp sensor and fans activate so we know the fans and relays are good. What happens if you disconnect the high pressure sensor and put a jumper in terminals fans should come on then if they do then either the sensor is bad or your not building enough head pressure to require fans. Does your ac cool if your going down the road?
LEtr me look up right quick
jump the gray to the red and black
those pressure readings you gave me is that as high as the high side gets
and does your ac cool if driving on road
Sir i am sorry my internet has been down can i still help you
With everything plugged up, i know the fans dont come on but if you drive the car down the road does the ac cool