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Scan Tool Data Definitions

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

The HVAC Scan Tool Data Definitions contain a brief description of all the scan tool parameters. This list is in alphanumeric order.

A/C High Side Pressure: The scan tool displays -103 to +3119 kPa (-14 to +452 psi). This parameter represents the A/C refrigerant pressure sensor voltage signal converted to pressure.

A/C High Side Pressure: The scan tool displays 0.00-5.00 Volts. This parameter represents the A/C refrigerant pressure sensor signal.

A/C Off For WOT: The scan tool displays Yes or No. Yes indicates that the PCM/ECM has disabled the A/C compressor because the TP sensor signal is at wide open throttle.

A/C Pressure Disable: The scan tool displays Yes or No. Yes indicates that the PCM/ECM has disabled the A/C compressor due to excessive refrigerant pressure.

A/C Request: The scan tool displays Yes or No. The PCM/ECM uses the A/C request signal in order to determine if A/C compressor operation is being requested by the HVAC control module.

A/C Request Signal: The scan tool displays Yes or No. The PCM/ECM uses the A/C request signal in order to determine if A/C compressor operation is being requested by the HVAC control module.

A/C Relay Command: The scan tool displays On or Off. Represents the PCM/ECM commanded state of the A/C compressor clutch relay. The A/C compressor clutch should be engaged when Commanded A/C displays On.

Ambient Air Temperature: The scan tool displays -50 to +87.5°C (-58 to +189.5°F). The output of the ambient air temperature sensor.

Auto Mode: The scan tool displays On or Off. When in Auto mode the scan tool displays On. When in Manual mode the scan tool displays Off.

Auto Button: The scan tool displays On or Off. When the AUTO button is pressed the scan tool displays On. When released, the scan tool displays Off.

Blower Speed: The scan tool displays 0 to 8 bars. When the blower motor is commanded off the scan tool displays 0. When the blower motor controls are placed in the maximum speed setting the scan tool displays 8 bars. This coincides with the HVAC control module display.

Evaporator Temp: This data displays -40 to 87.5°C (-40 to 189.5°F). The output of the evaporator temperature sensor.

Fan Down Button: The scan tool displays On or Off. When the Blower Speed Control Down button is pressed the scan tool displays On. When released, the scan tool displays Off.

Fan Up Button: The scan tool displays On or Off. When the Blower Speed Control Up button is pressed the scan tool displays On. When released, the scan tool displays Off.

Front Defrost Button: The scan tool displays On or Off. When the Front Defrost button is pressed the scan tool displays On. When released, the scan tool displays Off.

Inside Air Temperature: The scan tool displays -50 to +87.5°C (-58 to +189.5°F). The output of the inside air temperature sensor.

Left Temp Door Position: The scan tool displays 0 to 195 counts. The signal output from the feedback pot on the actuator.

Mode Button: The scan tool displays On or Off. When the Mode button is pressed the scan tool displays On. When released, the scan tool displays Off.

Mode Door Position: The scan tool displays Vent, Mix-Blend, Floor, Bi-Level or Defrost. The current operating mode of the HVAC system.

Off Button: The scan tool displays On or Off. When the Off button is pressed the scan tool displays On. When released, the scan tool displays Off.

Rear Defrost Button: The scan tool displays On or Off. When the Rear Defrost button is pressed the scan tool displays On. When released, the scan tool displays Off.

Recirculate Button: The scan tool displays On or Off. When the Recirculate button is pressed the scan tool displays On. When released, the scan tool displays Off.

Recirculation Mode: The scan tool displays Ambient Air or Recirculate. The current operating state of the recirculation door.

Right Temp Door Position: The scan tool displays 0 to 195 counts. The signal output from the feedback pot on the actuator.

Selected Air Mode: The scan tool displays Warm Up, Defrost or Off. The current operating mode of the HVAC system.

Sun Load Sensor: The scan tool displays 0 to 255 counts. The signal output from the Sun Load Sensor.

Vent Button: The scan tool displays On or Off. When the Vent button is pressed the scan tool displays On. When released, the scan tool displays Off.