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

Yes/No

Yes

AC Pressure

A/C Compressor Data

kPa/psi

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

Mode Dr. Actual

HVAC Door Positions

Counts/Volts

Varies

Mode 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

Low Coolant Status

HVAC System Data

OK/Low

OK

Low Coolant Switch

HVAC System Data

Open/Closed

Closed

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

Engine Data 2

kPa/Psi

629-845 kPa (85-120 psi)

A/C High Side Pressure

Engine Data 2

Volts

Varies

A/C Relay Command

Engine Data 2

On/Off

Varies

A/C Request Signal

Engine Data 2

Yes/No

Varies

ECT Sensor

Engine Data 2

°C/°F

92°C (197°F)

ECT Sensor

Engine Data 2

Volts

1.10-1.45 Volts