Challenger V8-5.7L (2010)
Refrigerant Pressure Sensor / Switch: Description and Operation
A/C Pressure Transducer - Operation
OPERATION
The A/C pressure transducer monitors the pressures in the high side of the refrigerant system through its connection to a fitting on the A/C liquid line.
The A/C pressure transducer will change its internal resistance in response to the pressures it monitors. A Schrader-type valve in the liquid line fitting
permits the A/C pressure transducer to be removed or installed without disturbing the refrigerant in the A/C system.
The totally integrated power module (TIPM) provides a five volt reference signal and a sensor ground to the A/C pressure transducer. The powertrain
control module (PCM) monitors the output voltage of the A/C pressure transducer on the CAN B bus to determine refrigerant pressure. The PCM is
programmed to respond to the A/C pressure transducer and other sensor inputs and control the operation of the A/C compressor clutch and the radiator
cooling fan to help optimize A/C system performance and to protect the system components from damage. The PCM will disengage the A/C compressor
clutch when high side pressure rises above 3082 kPa (447 psi) and re-engage the clutch when high side pressure drops below 2937 kPa (426 psi). The
A/C pressure transducer will also disengage the A/C compressor clutch if the high side pressure drops below 110 kPa (16 psi) and will re-engage the
clutch when the high side pressure rises above 221 kPa (32 psi). If the refrigerant pressure rises above 1655 kPa (240 psi), the PCM will actuate the
cooling fan. The A/C pressure transducer input to the PCM will also prevent the A/C compressor clutch from engaging when ambient temperatures are
below about 4.5° C (40° F) due to the pressure/temperature relationship of the refrigerant.
The A/C pressure transducer is tested using a scan tool See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Diagnostic
Trouble Code Tests and Associated Procedures.
The A/C pressure transducer cannot be adjusted or repaired and must be replaced if inoperative or damaged.
