A/C Clutch: Notes

On many models, ECM regulates operation of the A/C clutch through an ECM-controlled relay. The ECM 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 freon pressure drops to less than or rises to greater than normal operating levels.

Freon 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 ECM CONTROLS in I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.