A/C Clutch: Notes

1987 Chevrolet Hi-Cube 6.2 J, 400/M40SECTION Notes
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On many models, PCM regulates operation of the A/C clutch through an PCM-controlled relay. The PCM disengages the A/C compressor when compressor load on engine may cause driveability problems (i.e., during hot restart, idle, low speed steering maneuvers and wide open throttle operation) or if A/C refrigerant pressure drops to less than or rises to greater than normal operating levels.

Refrigerant pressure is sensed through the monitoring of high and low pressure switches or a pressure sensor which registers either high or low pressure levels. Power steering load is monitored through a power steering pressure switch (2.5L). Hot restart is monitored through the coolant temperature sensor. For component application and related wiring, see wiring schematics under MISCELLANEOUS PCM CONTROLS in SYSTEM/COMPONENT TESTS - GASOLINE article in the ENGINE PERFORMANCE section.

RENDER: 1.0x

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