For 1990-2009 cars

### HVAC Control Module Scan Tool Output Controls

Scan Tool Output Control | Additional Menu Selections | Description
--- | --- | ---
Air Inlet Door Position | HVAC Motors | When you select Outside, the HVAC control module commands the recirculation actuator toward the outside air position. When you select Recirculation, the HVAC control module commands the recirculation actuator toward the recirculation position.
Blower Motor | Miscellaneous Test | 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.
Driver Temp Door Position | HVAC Motors | When you select Cold, the HVAC control module commands the driver air temperature actuator to the full cold position. When you select Hot, the HVAC control module commands the actuator to the full hot position.
Mode Door Position | HVAC Motors | When you select A/C, the HVAC control module commands the mode actuator to the face position. When you select Defrost, the HVAC control module commands the actuator to the defrost position.
Passenger Temp Door Position | HVAC Motors | When you select Cold, the HVAC control module commands the passenger air temperature actuator to the full cold position. When you select Hot, the HVAC control module commands the actuator to the full hot position.

### HVAC Scan Tool Data Parameters

Parameter | Operating Conditions | Expected Value | Definition
--- | --- | --- | ---
Ignition is ON, engine OFF, and vehicle is stationary
A/C Compressor Current | -- | 0.008 A | This parameter displays the current of the air conditioning (A/C) Compressor.
A/C Compressor PWM | -- | 0 - 100% | This parameter displays the percentage of power supplied to the A/C compressor.
A/C Mode Request | -- | Disengaged | The scan tool displays Engage or Disengage. Engaged is displayed if the A/C is requested.
-- | Engaged
A/C 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 Switch | A/C button pressed | Active | The scan tool displays Active or Inactive. The scan tool displays Active when the A/C request switch is On. The scan tool displays Inactive when the A/C request switch is Off.
A/C button depressed | Inactive
Actual Air Mix Door Position | -- | 0 - 100% | This displays 0 - 100%. The actual position of air mix door is interpreted as a percentage by the HVAC control module.
Actual Front Demister Door Pos. | -- | 0 - 100% | The scan tool displays 0 - 100 %. The actual position of the front demister door is interpreted as a percentage by the HVAC control module.
Actual Recirculation Door Position | -- | 0 - 100% | The scan tool displays 0 - 100 %. The actual position of the recirculation door is interpreted as a percentage by the HVAC control module.
Actual Vent/Floor Outlet Door Pos. | -- | 0 - 100% | The scan tool displays 0 - 100 %. The actual position of the vent/floor outlet door interpreted as a percentage by the HVAC control module.
Backup System Power Mode | Backup system power mode activated | Enable | This parameter displays the status of the backup system power mode
Backup system power mode deactivated | Disable
Battery Voltage | -- | 0 - 25 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 Fan Speed Dial | User Dependent | 0 - 100% | The scan tool displays 0 - 100%. The speed of the blower motor is interpreted as a percentage.
Blower Fan Speed PWM | -- | 0 - 114% | The scan tool displays 0 - 114%. The scan tool displays the control decision for the blower motor speed as determined by the HVAC control module. The scan tool displays 114% when the blower motor is commanded to maximum speed and 0% when the blower motor is commanded Off.
Blower Fan Speed Voltage | -- | 1.4 Volts | The scan tool displays a voltage. The scan tool displays the control decision for the blower motor speed as determined by the HVAC control module. The scan tool displays 1.4 Volts when the blower motor is commanded to maximum speed and 0 Volts when the blower motor is commanded Off.
Commanded Air Mix Door Position | -- | 0 - 100% | The scan tool displays 0 - 100%. The commanded position of the air mix door interpreted as a percentage by the HVAC control module.
Commanded Front Demister Door Pos. | -- | 0 - 100% | The scan tool displays 0 - 100%. The commanded position of the front demister door interpreted as a percentage by the HVAC control module.
Commanded Recirculation Door Pos. | -- | 0 - 100% | The scan tool displays 0 - 100 %. The commanded position of the recirculation door interpreted as a percentage by the HVAC control module.
Commanded Vent/Floor Outlet Door Pos. | -- | 0 - 100% | The scan tool displays 0 - 100 %. The commanded position of the vent/floor outlet door interpreted as a percentage by the HVAC control module.
Engine Coolant Temp | -- | 18 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.
Engine ECU A/C Compressor Command | -- | Allowed | This parameter indicates permission to turn On the A/C Compressor from the ECM. The scan tool displays Allowed or Not Allowed.
-- | Not Allowed
Engine Speed | -- | 0 RPM | The scan tool displays the speed of the engine in RPM.
Evaporator Target Temp | -- | -40 degrees | This parameter displays the target temperature of the evaporator as set by the HVAC control module
Evaporator Temp | -- | 15 degrees | This parameter displays the current temperature of the evaporator
Evaporator Temp | -- | 15.5 degrees | This parameter displays the current temperature of the evaporator
Front Outlet Mode | User dependent | Compartment | The scan tool displays Compartment, Compartment/Floor, Floor, Floor/Demister or Demister. This is the front outlet mode as interpreted by the HVAC control module.
Compartment/Floor
Floor
Floor/Demister
Demister
Inlet Mode | Recirculation button pressed | Recirculation | The scan tool displays Fresh or Recirculation. This is the inlet mode as interpreted by the HVAC control module.
Recirculation button depressed | Fresh
Mode Dial | Mode Dial in Compartment position | Compartment | The scan tool displays Floor, Compartment or Demister. This is the outlet mode as selected by the user and is interpreted by the HVAC control module.
Mode Dial in Compartment/Floor position | Compartment/Floor
Mode Dial in Floor position | Floor
Mode Dial in Floor/Demister position | Floor/Demister
Mode Dial in Demister position | Demister
Rear Window Demister | Rear window demister activated | Active | The scan tool displays the status of the rear window demister, Active when the rear window demister is activated and Inactive when the rear window demister is deactivated.
Rear window demister deactivated | Inactive
Rear Window Demister Switch | Rear window demister switch activated | Active | The scan tool displays the current position of the rear window demister switch, Active when the rear window demister switch is activated and Inactive when the rear window demister switch is deactivated.
Rear window demister switch deactivated | Inactive
Recirculation Switch | Recirculation switch activated | Active | The scan tool displays the current position of the recirculation switch, Active when the recirculation switch is activated and Inactive when the recirculation switch is deactivated.
Recirculation switch deactivated | Inactive
System 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
Temperature Dial | -- | 0 - 100% | The scan tool displays 0 - 100%. The temperature position is commanded by the user and is interpreted as a percentage by the HVAC control module.
Vehicle Speed | -- | 0km | The scan tool range is 0 - 255 km/h (0 - 158 mph). This parameter indicates the vehicle speed calculated by the ECM from the vehicle speed sensor (VSS).