GM Service Manual Online
For 1990-2009 cars only

HVAC Control Module Scan Tool Data List

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F)

A/C LED

System Data

Off/On

Varies

A/C Head Pressure

A/C Permission Data

Normal/Out of Range

Normal

A/C Permission

A/C Permission Data

Withheld/Granted

Varies

A/C Request

A/C Permission Data

No/Yes

Varies

A/C Switch

System Data

Inactive/Active

Varies

Ambient Air Temperature

A/C Permission Data

Normal/Out of Range

Normal

Air Inlet Door Actual

Door Positions

Counts

Varies

Air Inlet Door Commanded

Door Positions

0 --255 Counts

Varies

Auxiliary Blower Motor PWM

System Data

%

Varies

Auxiliary LED

System Data

Off/On

Varies

Auxiliary Mode Door Commanded

Door Positions

0 --255 Counts

Varies

Auxiliary Mode Switch Position

Inputs

Panel/Bilevel/Floor

Varies

Auxiliary Switch

Inputs

Inactive/Active

Varies

Auxiliary Temp Door Motor Command

Door Positions

0 --255 Counts

Varies

Battery Voltage

A/C Permission

Normal/Out of Range

Normal

Blower Speed

A/C Permission

Normal/Off

Varies

Blower Motor Speed Command

System Data

%

Varies

Driver Heated Seat LED

System Data

Off/On

Off

Driver Heated Seat Status

System Data

Off/Low/High

Off

Driver Heated Seat Switch

Inputs

Inactive/Active

Inactive

Engine Coolant Temp

A/C Permission

Normal/Out of Range

Normal

Engine Running

A/C Permission

Yes/No

Varies

Inside Air Temp Sensor

Sensors

°C

Varies

Left Hand A/C Duct Actual Temp

Sensors

°C

Varies

Left Hand A/C Duct Desired Temp

Sensors

°C

Varies

Left Hand Heater Duct Actual Temp

Sensors

°C

Varies

Left Hand Heater Duct Desired Temp

Sensors

°C

Varies

Left Temp Door Commanded

Door Positions

0-255 count

Varies

Left Sunload Sensor

Sensors

Counts

Varies

Low Pressure Switch

System Data

Open/Close

Close

Low Coolant Switch

System Data

Open/Close

Close

Mode Switch Position

Inputs

Auto/Panel/Bi-Level/Floor/Defrost-Floor

Varies

Mode Door Actual

Door Positions

Counts

Varies

Mode Door Commanded

Door Positions

0-255 Count

Varies

Outside Air Temp Filtered

Sensors

°C

Varies

Outside Air LED

System Data

Off/On

Varies

Outside Air Temp RAW

Sensors

°C

Varies

Outside Air Mode Switch

Inputs

Inactive/Active

Varies

Passenger Heated Seat Status

System Data

Off/Low/High

Off

Passenger Heated Seat Switch

Inputs

Inactive/Active

Inactive

Passenger Heated Seat LED

System Data

Off/On

Off

Rear Defrost LED

System Data

Off/On

Off

Rear Defrost Switch

Inputs

Inactive/Active

Inactive

Rear Defrost State

System Data

Off/On

Off

Recirculation Switch

Inputs

Inactive/Active

Inactive

Right Sunload Sensor

Sensors

Counts

Varies