Air Conditioning

AIR CONDITIONING

The air conditioning system components are:
- A/C compressor
- A/C condenser core
- A/C evaporator core
- Suction accumulator
- Connecting refrigerant lines
- Evaporator core orifice
- A/C cycling switch
- A/C pressure transducer (4.0L)
- Dual-function pressure switch (4.6L and 5.4L)
- A/C compressor pressure relief valve

The refrigerant system incorporates an A/C compressor controlled by the powertrain control module (PCM) through an A/C clutch relay.

The A/C compressor clutch will only be engaged by the PCM if all of the following conditions are met:
- The climate control assembly is set to a mode which provides an A/C request to the PCM.
- The A/C cycling switch is not open due to excessively low suction pressure in the low-pressure side of the refrigerant system.
- The A/C pressure transducer is not reading excessively high discharge pressure in the high-pressure side of the refrigerant system (4.0L).
- The dual-function pressure switch is not open due to excessively high discharge pressure in the high-pressure side of the refrigerant system (4.6L and 5.4L).
- The A/C compressor relay is switched to the closed position by the PCM.
- The engine coolant temperature is not excessively high.
- The PCM has not detected a wide open throttle (WOT) condition.

An A/C compressor pressure relief valve is installed in the compressor manifold and tube assembly (4.0L vehicles) or the A/C compressor (4.6L or 5.4L vehicles) to protect the refrigerant system against excessively high refrigerant pressures.

Refrigerant flow into the evaporator core is metered by an evaporator core orifice tube.