GM Service Manual Online
For 1990-2009 cars only
Table 1: HVAC Control Module Scan Tool Data List
Table 2: ECM Scan Tool Data List

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 Clutch-Actual

A/C Compressor Data

On/Off

On

A/C Clutch-Desired

A/C Compressor Data

Engage/Disengage

Yes

AC Pressure

A/C Compressor Data

kPa/psi

Varies

Air Inlet Door Actual

HVAC Door Positions

Recirc/Fresh Air

Varies

Commanded Blower

HVAC System Data

%

Varies

Coolant Temperature

HVAC System Data

°C/°F

Varies

Driver Temp. Dr. Actual

HVAC Door Positions

Counts/Volts

Varies

Driver Temp. Dr. Commanded

HVAC Door Positions

Counts/Volts

Varies

Driver Solar Sensor

Open/Short Data

Counts/Volts

Varies

Driver Sunload

HVAC System Data

w/m2

Varies

Evaporator Temp

HVAC System Data

°C/°F

Varies

Evaporator Temp

A/C Compressor Data

°C/°F

Varies

Evaporator Temp

Open/Short Data

Counts/Volts

Varies

Htr./Def./A/C Dr. Actual

HVAC Door Positions

Counts/Volts

Varies

Htr./Def./A/C Dr. Commanded

HVAC Door Positions

Counts/Volts

Varies

Inside Air Temp

HVAC System Data

°C/°F

Varies

Inside Air Temp

Open/Short Data

Counts/Volts

Varies

Outside Air Temp

HVAC System Data

°C/°F

Varies

Outside Air Temp

Open/Short Data

Counts/Volts

Varies

Passenger Solar Sensor

Open/Short Data

Counts/Volts

Varies

Passenger Sunload

HVAC System Data

w/m2

Varies

Passenger Temp Dr. Actual

HVAC Door Positions

Counts/Volts

Varies

Passenger Temp Dr. Commanded

HVAC Door Positions

Counts/Volts

Varies

Pressure Sensor

A/C Compressor Data

OK/Failed

OK

Vehicle Speed

HVAC System Data

Km/h/mph

Varies

ECM 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 High Side Pressure

Cooling HVAC Data

kPa/Psi

629-845 kPa (85-120 psi)

A/C High Side Pressure

Cooling HVAC Data

Volts

Varies

A/C Relay Command

Engine Data 1, Cooling HVAC Data

On/Off

Varies

A/C Request Signal

Cooling HVAC Data

Yes/No

Varies

ECT Sensor

Engine Data 1, Cooling HVAC Data

°C/°F

92°C (197°F)

ECT Sensor

Engine Data 1, Cooling HVAC Data

Volts

1.10-1.45 Volts