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Refrigerant Pressure Sensor / Switch: Testing and Inspection

ELECTRONIC CYCLING CLUTCH SWITCH (ECCS)











The ambient temperature in the test area should be approximately 21 C° (70 F°) while testing. Supply +12 (+-1) volts to pin 2 of the 3 pin ECCS connector. Ground pin 3, and connect the output, pin 1, through a 399 ohm resistance to the +12 volt supply.

CAUTION: Do not connect pin 1 directly to the +12 volt supply.

The voltage measured at the output (pin 1), when referenced to switch ground should be 0.75 volts or less. If the voltage at pin 1 exceeds 0.75 volts, replace the ECCS.