Where is low pressure cut out switch on ac 2000 Malibu?

Answer 1

There is no low pressure cutout switch on the 1997-2001 Chevrolet Malibu. This holds true for both L4 cyl and V6 cyl models of this regardless of two door or four door. There also is not a high pressure cutout switch, but there is a pressure switch on the high side line at the top of the condensor, on the aluminum line coming from the condensor to the A/C compressor. Most parts stores will find it listed as a high pressure switch, but it actually is a transducer switch that works off the high pressure side. The compressor clutch engage and disengage functions are controlled by the on-board computer. It sends a 5 volt reference signal to the pressure transducer switch and the switch modulates the return voltage back to the on-board computer. The on-board computer reads that voltage change and determines if the high side pressure is within a certain range. If it is below that range then the on-board computer grounds the A/C clutch relay in the relay/fuse box on the driver-side under the hood, which in turn puts 12 volts to the A/C clutch engaging the compressor. Once the high side pressure reaches a certain point and the voltage return from the pressure transducer switch to the on-board computer is above a certain range, then the on-board computer removes the ground from the A/C clutch relay, which removes the 12 volts to the A/C clutch and it disengages.

This particular system of controlling the A/C clutch/compressor cycling is used on many of the vehicles GM has been building since 1994. The set up of the system varies from vehicle to vehicle, but almost all of them control the compressor from a switch used on the high side pressure line.