The HVAC Scan Tool Data Definitions contains a brief description of all HVAC related parameters available on the scan tool. The list is in alphabetical order. A given parameter may appear in any one of the data lists. In some cases, the parameter may appear more than once or in more than one data list in order to group certain related parameters together.

PCM -- A/C Pressure Sensor: The scan tool displays 0-3450 kPa (0-500 psi). The voltage applied to the PCM input from the A/C refrigerant pressure sensor is converted to a pressure value.

PCM -- A/C Pressure Sensor: The scan tool displays 0-5 volts. The voltage applied to the PCM input for the A/C refrigerant pressure sensor.

PCM -- A/C Relay Command: The scan tool displays On or Off. This parameter displays the PCM commanded state of the A/C compressor clutch relay. When the scan tool displays ON, the A/C compressor clutch should be engaged.

PCM -- A/C Request: The scan tool displays Yes or No. The A/C Request displays the state of the A/C request input from the Roof/Door Module. The powertrain control module (PCM) uses the A/C request in order to determine whether the A/C compressor operation is being requested.

RDM -- A/C Request : The scan tool displays Yes or No. The A/C Request displays the state of the A/C request input circuit from the heating, ventilation, and air conditioning (HVAC) controls. The Roof/Door module uses the A/C request signal in order to determine whether the A/C compressor operation is being requested.