Auto Air Conditioning & Heater Repair: 1995 geo prism A/c clutch, 1995 geo prism, compressor clutch

Question
QUESTION: I need to know if the A/C amplifer would cause the compressor clutch not to cycle on and off? I have replaced all the relays & fuses that I can find for A/c .Still no clutch cycling. Thank you very much for your help. Johnny

ANSWER: Hi Johnny

Need to check for pressure in the system first.  System needs to have at least 50psi for compressor to engage.  Then check your a/ac thermostat located near the evaporator case. see if ground is getting through.

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QUESTION: I have changed a/c compressor with clutch, drier, expansion valve,relays and fuses,so no pressure yet.can you give me a hint to what I am looking for when you say thermostat.On the evaparator there is a black wiring connector and a white wiring connector and they are located on the top of the evap.case/ Thanks Johnny

Answer
You must add refrigerant in order for the compressor will engage.  At the evap. you will see a metal or plastic prode looking piece.  That is the thermostat you will have two wires jump them and see if compressor starts.  But remember you must first add refrigerant to the system.