Evaporator Temperature Sensor / Switch: Description and Operation

PURPOSE
The evaporator temperature regulator (ETR) controls compressor cutout when evaporator temperature drops below freezing temperature 0°C (32°F).

OPERATION
During cooling operation of the automatic climate control (ACC) system, the ETR switch interrupts compressor clutch relay (code 12) actuating coil when the evaporator temperature drops below 0°C (32°F).