Compressor Control Logic

The A/C compressor and engine cooling fan will be control led by PCM/ECM/BCM control logic under the following conditions

Coolant Temperature
^ Disabled if engine coolant temperature exceeds 117°C (243°F).
^ Enabled when coolant temperature is 114°C (237°F).

A/C System Pressure

High
^ Disabled if A/C system pressure exceeds 2940 kPa (426 psi).
^ Enabled when A/C system pressure is 2062 kPa (299 psi).

Low
^ Disabled if A/C system pressure goes below 211 kPa (31 psi).
^ Enabled when A/C system pressure goes above 258 kPa (37 psi).

Evaporator Low Ambient Protection (ELAP)
The refrigerant temperature at the temperature sensor in the TXV controls cycling of the compressor clutch to prevent freezing of the evaporator core. The compressor Is disabled when the temperature goes below 3°C (37°F). The compressor is enabled when the temperature exceeds 4°C (40°F). The minimum time off is 4 seconds.

Compressor Engagement During Engine Crank
The compressor clutch is engaged during engine cranking to cycle oil through the A/C system. The clutch is engaged when the engine speed is above 160 rpm, coolant temperature is below 47°C (116°F), intake air temperature is above 8°C (47°F), A/C pressure is above 258 kPa (37 psi), and battery voltage is above 9.5 volts.