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Home >> Oldsmobile >> 1993 >> Ninety-Eight V6-3800 3.8L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> A/C Signal >> Description and Operation >> A/C Pressure Cycling Switch
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A/C Pressure Cycling Switch

A/C Control Circuit Diagram (Electronic And Dual Zone A/C):





ELECTRONIC AND DUAL ZONE A/C

A/C Control Circuit Diagram (Manual A/C):





MANUAL A/C


The A/C pressure cycling switch, located on the accumulator, is a normally open switch that closes when there is sufficient refrigerant charge (greater than approx. 25 psi). When the A/C control switch is turned "ON" and the pressure cycling switch is closed, a request signal is sent to the PCM, which energizes the A/C compressor clutch.
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