GM Service Manual Online
For 1990-2009 cars only

Heating Ventilation Air Conditioning Scan Tool Data Parameters

Parameter

Operating Conditions

Expected Value

Definition

Ignition is ON, engine OFF, and vehicle is stationary

A/C Head Pressure

--

448 kpa

The scan tool displays 0-3450 kPa (0-500 psi). The voltage applied to the BCM input from the A/C refrigerant pressure sensor is converted to a pressure value.

A/C Head Pressure

--

Normal

The scan tool displays Normal or Out of Range. This is the state of the A/C head pressure.

--

Out of Range

A/C Permission

--

Granted

The scan tool displays Granted or Withheld. This is the state of the A/C.

--

Withheld

A/C Request

A/C button pressed

Yes

The scan tool displays Yes or No. The scan tool displays Yes when the A/C request switch is on. The scan tool displays No when the A/C request switch is off.

A/C button depressed

No

Air Inlet Door Actual

--

%

This displays Counts. This is the current numeric value of the air inlet door as monitored by the HVAC module.

Air Inlet Door Commanded

--

%

This displays Counts. This is the numeric value of the air inlet door as commanded by the HVAC module.

Aux. Mode Door Actual

--

%

This displays Counts. This is the current numeric value of the auxiliary mode door as monitored by the HVAC module.

Aux. Mode Door Commanded

--

%

This displays Counts. This is the numeric value of the auxiliary mode door as commanded by the HVAC module.

Battery Voltage

--

12 Volts

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 Relay Command

--

On

The scan tool displays On/Off. When you select ON, the HVAC control module commands the blower motor relay ON. When you select OFF, the HVAC control module commands the blower motor relay OFF.

--

Off

Blower Motor Speed

--

%

This displays percent. This is the percentage of power supplied to the blower motor.

Blower Speed

--

Normal

The scan tool displays Normal or Off. This is the state of the blower motor speed.

--

Off

Compressor Performance Test Status

--

Active

 

--

Not Active

Coolant Temperature

--

Degrees

The scan tool displays -39 to +140°C (-38 to +284°F). The scan tool displays the engine coolant temperature as detected by the ECM.

Driver Solar Sensor

--

W/m²

This displays W/m². This is an approximate value at the driver sunload sensor.

Driver Temp. Dr. Actual

--

%

This displays Counts. This is the current numeric value of the driver temperature door as monitored by the HVAC module.

Driver Temp. Dr. Commanded

--

%

This displays Counts. This is the numeric value of the driver temperature door as commanded by the HVAC module.

Driver Temp. Setting

--

Degrees

This displays °C (°F). This is the temperature setting of the driver side area.

Evaporator Temp

--

15.5 degrees

This parameter displays the current temperature of the evaporator

Inside Air Temp. Filtered

--

Degrees

This displays °C (°F). This is the current temperature of the vehicle interior.

Mode Door Actual

--

%

This displays Percentage. This is the current numeric value of the mode door as monitored by the HVAC module.

Mode Door Commanded

--

%

This displays Percentage. This is the numeric value of the mode door as commanded by the HVAC module.

Outside Air Temperature Filtered

 

°

This displays °C (°F). This is the current temperature of the air outside.

Passenger Solar Sensor

--

W/m²

This displays W/m². This is an approximate value at the passenger sunload sensor.

Passenger Temp. Dr. Actual

--

%

This displays Counts. This is the current numeric value of the passenger temperature door as monitored by the HVAC module.

Passenger Temp. Dr. Commanded

--

%

This displays Counts. This is the numeric value of the passenger mode door as commanded by the HVAC module.

Passenger Temp. Setting

--

Degrees

This displays °C (°F). This is the temperature setting of the passenger side area.

Power Mode

Ignition is in OFF position

OFF

The scan tool displays the system power mode which is dependent on the current position of the ignition cycle.

Ignition is in ACC position

Accessory

Ignition is in RUN position

Run

Ignition is in CRANK position

Crank

Rear Defog Relay

--

Active

The scan tool displays Active or Inactive. This is the state of the rear defrost switch.

--

Inactive

Remote Start Status

--

Active

The scan tool displays Active or Inactive.

--

Inactive

Heating Ventilation Air Conditioning Control Module Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selections

Description

A/C Compressor Performance

Special Function

 

Air Inlet Door

Special Function

The scan tool displays On or Off selections. The selection drives the actuator to its minimum or maximum positions.

Aux. Mode Door

Special Function

The scan tool displays On or Off selections. The selection drives the actuator to its minimum or maximum positions.

Blower Motor Relay

Miscellaneous Test

The scan tool commands the blower motor relay On or Off. When you select ON, the HVAC control module commands the blower motor relay ON. When you select OFF, the HVAC control module commands the blower motor relay OFF.

Blower Motor

Miscellaneous Test

The scan tool commands the blower motor On or Off. When ON is selected, the HVAC control module commands the blower motor relay ON and a command to increase or decrease air. When OFF is selected, the HVAC control module commands the blower motor relay OFF.

Driver Temp. Dr.

Special Function

The scan tool displays On or Off selections. The selection drives the actuator to its minimum or maximum positions.

Mode Door position

Special Function

The scan tool displays On or Off selections. The selection drives the actuator to its minimum or maximum positions.

Passenger Temp. Dr. Commanded

Special Function

The scan tool displays On or Off selections. The selection drives the actuator to its minimum or maximum positions.

Rear Defog Request

Special Functions

The scan tool commands the rear defog Active or Inactive.