Scan Tool Data Definitions

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A/C High Side Pressure: 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.
A/C High Side Pressure: The scan tool displays 0-5 volts. The voltage applied to the PCM input for the A/C refrigerant pressure sensor.
A/C Relay Command: The scan tool displays On/Off. The scan tool displays the control decision for the compressor clutch relay output as determined by the PCM.
A/C Request Signal: The scan tool displays Yes/No. The scan tool displays Yes when the PCM receives a class 2 message from the HVAC control module to engage the A/C compressor clutch. The scan tool displays No when the PCM receives a class 2 message from the HVAC control module to disengage the A/C compressor clutch.
A/C Switch: The scan tool displays On/Off. The scan tool displays On when the A/C request switch is active. The scan tool displays Off when the A/C request switch is inactive.
AC Permission: The scan tool displays Withheld/Granted. The scan tool displays Granted when the HVAC control module determines that conditions for compressor clutch engagement are present. The scan tool displays Withheld when the HVAC control module determines that conditions for compressor clutch engagement are not present.
Air Inlet Door Actual: The scan tool displays 0-255 counts. The voltage applied to the recirculation door position input of the HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Air Inlet Motor Drive: The scan tool displays Stop, Increase, or Decrease. The scan tool displays the control decision for the actuator output as determined by the HVAC control module.
Air Mix Door Left Commanded: The scan tool displays 0-255 counts. The scan tool displays the desired left air temperature door position as determined by the HVAC control module.
Air Mix Door Right Commanded: The scan tool displays 0-255 counts. The scan tool displays the desired right air temperature door position as determined by the HVAC control module.
Air Temp. Switch Pos.: The scan tool displays a numeric value between 0-18. The lower the numeric value the lower the temperature that is selected. The numeric value is a reading of the voltage signal applied to the input of the front auxiliary temperature switch to the auxiliary HVAC control module
Ambient Air Temp. Sensor: The scan tool displays -40 to +215°C (-40 to +419°F). The current value of the ambient air temperature display on the HVAC control module.
Auto Switch: The scan tool displays On/Off. The scan tool displays On when the automatic switch is active. The scan tool displays Off when the automatic switch is inactive.
Aux. Temp Dr. Motor Command: The scan tool displays 0-255 counts. The scan tool displays the desired auxiliary air temperature door position as determined by the auxiliary HVAC control module.
Aux. Temp Dr. Motor Status: The scan tool displays Stop, Increase, or Decrease. The scan tool displays the control decision for the actuator output as determined by the auxiliary HVAC control module.
Aux. Temp Dr. Position: The scan tool displays 0-255 counts. The voltage applied to the auxiliary air temperature door position input of the auxiliary HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Battery Voltage: The scan tool displays 0-25 volts. The voltage measured from the battery positive voltage circuit and the ground circuit of the HVAC control module.
Blower Motor PWM Speed: The scan tool displays 0-114%. The scan tool displays the control decision for the blower motor speed as determined by the HVAC control module. The scan tool displays 114% when the blower motor is commanded to maximum speed. The scan tool displays 0% when the blower motor is commanded OFF.
Blower Switch Pos.: The scan tool displays a numeric value between 0-15. Position 0 is the AUTO position. Position 1 is the AUX. position. Position 2 turns off the auxiliary controls. Positions 3-15 are the auxiliary blower motor speed positions. The lower the number the lower the auxiliary blower motor speed input. The numeric value is a reading of the voltage signal applied to the input of the front auxiliary blower motor switch to the auxiliary HVAC control module.
ECT Sensor: The scan tool displays -39 to +140°C (-38 to +284°F). The voltage applied to the PCM input from the engine coolant temperature sensor is converted to a temperature value.
ECT Sensor: The scan tool displays 0-5 volts. The voltage applied to the PCM input for the engine coolant temperature sensor.
Engine Coolant Temp: The scan tool displays -39 to +140°C (-38 to +284°F). The scan tool displays the engine coolant temperature as detected by the PCM.
Fan Down Button: The scan tool displays On/Off. The scan tool displays On when the fan down switch is active. The scan tool displays Off when the fan down switch is inactive.
Fan Up Button: The scan tool displays On/Off. The scan tool displays On when the fan up switch is active. The scan tool displays Off when the fan up switch is inactive.
Front Defrost Switch: The scan tool displays On/Off. The scan tool displays On when the defrost switch is active. The scan tool displays Off when the defrost switch is inactive.
Ign. Since Current DTC: The scan tool displays 0-100. The number of the ignition cycles since the setting of the most recent current diagnostic trouble code (DTC).
Inside Air Temp. Fan: The scan tool displays On/Off. The scan tool displays the control decision for the fan motor output as determined by the HVAC control module. The fan motor is internal to the inside air temperature sensor assembly.
Inside Air Temp.: The scan tool displays -40 to +215°C (-40 to +419°F). The voltage applied to the HVAC control module input for the inside air temperature sensor is converted to a temperature value.
Inside Air Temp. Fan: The scan tool displays On/Off. The scan tool displays the control decision for the fan motor output as determined by the auxiliary HVAC control module. The fan motor is internal to the auxiliary inside air temperature sensor assembly.
Inside Air Temp. Sensor: The scan tool displays 0-255 counts. The voltage applied to the auxiliary inside air temperature input of the auxiliary HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Left Mix Door Actual: The scan tool displays 0-255 counts. The voltage applied to the left air temperature door position input of the HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Left Mix Motor Drive: The scan tool displays Stop, Increase, or Decrease. The scan tool displays the control decision for the actuator output as determined by the HVAC control module.
Left Solar Sensor: The scan tool displays 0-255 counts. The voltage applied to the left sunload input of the BCM is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Left Temp. Setting: The scan tool displays 15-32°C (60-90°F). The scan tool displays the selected temperature from the left air temperature switch.
LH AC Duct Actual: The scan tool displays 0-255 counts. The voltage applied to the left upper duct air temperature input of the HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
LH AC Duct Desired: The scan tool displays 0-255 counts. The desired value of the left upper duct air temperature input. The HVAC control module monitors the actual value of the duct air temperature input and accordingly positions the left air temperature door to achieve the desired duct air temperature.
LH Heater Duct Actual: The scan tool displays 0-255 counts. The voltage applied to the left lower duct air temperature input of the HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
LH Heater Duct Desired: The scan tool displays 0-255 counts. The desired value of the left lower duct air temperature input. The HVAC control module monitors the actual value of the duct air temperature input and accordingly positions the left air temperature door to achieve the desired duct air temperature.
Lower Heater Duct Actual: The scan tool displays 0-255 counts. The voltage applied to the auxiliary lower air temperature sensor input of the auxiliary HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Mode Door Actual: The scan tool displays 0-255 counts. The voltage applied to the auxiliary mode door position input of the auxiliary HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Mode Motor Drive: The scan tool displays Stop, Increase, or Decrease. The scan tool displays the control decision for the actuator output as determined by the auxiliary HVAC control module.
Mode Dr. Motor Command: The scan tool displays 0-255 counts. The scan tool displays the desired auxiliary mode door position as determined by the auxiliary HVAC control module.
Mode Select Position: The scan tool displays Off, Auto, Defrost, Heater, Htr/Def, Bi-Level, Panel. The scan tool displays the state of mode operation.
Mode Switch: The scan tool displays On/Off. The scan tool displays On when the mode switch is active. The scan tool displays Off when the mode switch is inactive.
Mode Switch Pos.: The scan tool displays a numeric value between 0-17. Position 0 is the Auto position. Position 1 is the Panel position. Position 9 is the Bi-Level position. Position 17 is the Floor position. The numeric value is a reading of the voltage signal applied to the input of the front auxiliary mode switch to the auxiliary HVAC control module
Off Switch: The scan tool displays On/Off. The scan tool displays On when the Off switch is active. The scan tool displays Off when the Off switch is inactive.
Outside Air Temp. Filtered: The scan tool displays -40 to +215°C (-40 to +419°F). The current value of the ambient air temperature display on the HVAC control module.
Outside Air Temp. Raw: The scan tool displays -40 to +215°C (-40 to +419°F). The voltage applied to the HVAC control module input from the ambient air temperature sensor is converted to an unfiltered temperature value.
Pressure Cycle Switch: The scan tool displays Low Pressure/Normal. The current state of the input from the A/C low pressure switch. The scan tool displays Low Pressure when the switch is open and displays Normal when the switch is closed. The low pressure switch opens when low side pressure decreases to approximately 151 kPa (22 psi) and closes when the low side pressure increases to approximately 275 kPa (40 psi).
Rear HVAC Fan Down Sw.: The scan tool displays Active/Inactive. The scan tool displays Active when the fan down switch is active. The scan tool displays Inactive when the fan down switch is inactive.
Rear HVAC Fan Select Pos.: The scan tool displays Auto/Off/Low/Med/High. The scan tool displays the state of fan operation.
Rear HVAC Fan Speed: The scan tool displays Auto/Off/Low/Med/High. The scan tool displays the state of fan operation.
Rear HVAC Fan Up Switch: The scan tool displays Active/Inactive. The scan tool displays Active when the fan up switch is active. The scan tool displays Inactive when the fan up switch is inactive.
Rear HVAC Mode Select Pos.: The scan tool displays Auto/Floor/Bi-Level/ Panel. The scan tool displays the state of mode operation.
Rear HVAC Mode Switch: The scan tool displays Active/Inactive. The scan tool displays Active when the mode switch is active. The scan tool displays Inactive when the mode switch is inactive.
Recirculate Switch: The scan tool displays On/Off. The scan tool displays On when the recirculation switch is active. The scan tool displays Off when the recirculation switch is inactive.
RH AC Duct Actual: The scan tool displays 0-255 counts. The voltage applied to the right upper duct air temperature input of the HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
RH AC Duct Desired: The scan tool displays 0-255 counts. The desired value of the right upper duct air temperature input. The HVAC control module monitors the actual value of the duct air temperature input and accordingly positions the right air temperature door to achieve the desired duct air temperature.
RH Heater Duct Actual: The scan tool displays 0-255 counts. The voltage applied to the right lower duct air temperature input of the HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
RH Heater Duct Desired: The scan tool displays 0-255 counts. The desired value of the right lower duct air temperature input. The HVAC control module monitors the actual value of the duct air temperature input and accordingly positions the right air temperature door to achieve the desired duct air temperature.
Right Mix Door Actual: The scan tool displays 0-255 counts. The voltage applied to the right air temperature door position input of the HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Right Mix Motor Drive: The scan tool displays Stop, Increase, or Decrease. The scan tool displays the control decision for the actuator output as determined by the HVAC control module.
Right Solar Sensor: The scan tool displays 0-255 counts. The voltage applied to the BCM input from the right sunload sensor is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.
Right Temp. Setting: The scan tool displays 15 to 32°C (60 to 90°F). The scan tool displays the selected temperature from the right air temperature switch.
Upper Htr. Duct Actual: The scan tool displays 0-255 counts. The voltage applied to the auxiliary upper air temperature sensor input of the auxiliary HVAC control module is converted to a number between 0 and 255 where 51 counts is approximately equal to 1 V.