Heating, Ventilation & Air Conditioning Control Module Scan Tool Information
WARNING: This page is about a different car, the 2008 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
HVAC Control Module Scan Tool Data List
| Parameter | System Value | Expected Value | Description |
|---|---|---|---|
| Operating Conditions: Engine idling, A/C ON, ambient air temperature between 22-27°C (70-80°F) | |||
| A/C Evap. Temperature Sensor | - | Varies | The scan tool displays -39 to +140°C (-38 to +284°F). The voltage applied to the HVAC control module input from the evaporator temperature sensor is converted to a temperature value. |
| A/C High Side Pressure Sensor | - | Varies | The scan tool displays 0-5 volts. The voltage applied to the ECM input for the A/C refrigerant pressure sensor. |
| Ambient Air Temp. Sensor | - | Varies | 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. |
| Blower Motor Speed | - | Varies | The scan tool displays 0-100%. The scan tool displays the control decision for the blower motor speed as determined by the HVAC control module. The scan tool displays 100% when the blower motor is commanded to maximum speed. The scan tool displays 0% when the blower motor is commanded OFF. |
| Coolant Temperature | - | Varies | The scan tool displays -39 to +140°C (-38 to +284°F). The voltage applied to the ECM input from the engine coolant temperature sensor is converted to a temperature value and transmitted in a GMLAN message to the HVAC control module. |
| Driver Temp. Dr. Motor Commanded | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The desired position of the driver air temperature actuator as determined by the HVAC control module. |
| Driver Temp. Dr. Position | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The voltage applied to the driver air temperature door position input of the HVAC control module. |
| Inside Air Temp. Sensor | - | Varies | 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. |
| Left Sunload Sensor | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The voltage applied to the left sunload input of the HVAC control module. |
| Mode Dr. Motor Command | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The desired position of the mode actuator as determined by the HVAC control module. |
| Mode Door Position | - | Varies | The scan tool displays Off and On selections. The selection drives the actuator to its minimum and maximum positions when commanded in both directions. |
| Psgr. Temp. Dr. Motor Command | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The desired position of the passenger air temperature actuator as determined by the HVAC control module. |
| Psgr. Temp. Dr. Position | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The voltage applied to the passenger air temperature door position input of the HVAC control module. |
| Recirculation Dr. Motor Command | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The desired position of the recirc door actuator as determined by the HVAC control module. |
| Recirculation Dr. Position | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The voltage applied to the recirc door position input of the HVAC control module. |
| Right Sunload Sensor | - | Varies | The scan tool displays 0-255 counts (0-5.00 volts). The voltage applied to the right sunload input of the HVAC control module. |
| Vehicle Speed | - | Varies | The scan tool displays Km/h/mph |
HVAC Scan Tool Output Controls
| Output Control | Description |
|---|---|
| Blower Motor | The scan tool displays Off and On selections. The selection commands the blower speed to its minimum and maximum when commanded On and Off. |
| Driver Temp Door | The scan tool displays Off and On selections. The selection drives the actuator to its minimum and maximum positions when commanded in both directions. |
| Inside Air Temp. Sensor Fan | The scan tool displays On and Off. When the inside air temp. sensor fan is commanded On the inside air temp sensor fan scan tool parameter also displays On. |
| Mode Door Position | The scan tool displays Off and On selections. The selection drives the actuator to its minimum and maximum positions when commanded in both directions. |
| Passenger Temp Door | The scan tool displays Off and On selections. The selection drives the actuator to its minimum and maximum positions when commanded in both directions. |
| Rear Defog Request | The scan tool displays On and Off. When selected On the HVAC module activates the rear defogger. |
| Recirculation Door | The scan tool displays Off and On selections. The selection drives the actuator to its minimum and maximum positions when commanded in both directions. |
| Segment Check | The scan tool displays Off and On selections. When commanded Off the LCD display on the HVAC module is blank. When commanded back On the LCD displays all viewable numbers and symbols. |