Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Heating, Ventilation and Air Conditioning Control Module Scan Tool Information
2009 Chevrolet Uplander LT, 3.9 MSECTION Heating, Ventilation and Air Conditioning Control Module Scan Tool Information
HVAC Control Module Scan Tool Data Parameters
| Parameter | System State | Expected Value | Description |
|---|---|---|---|
| Operating Conditions: Ignition ON | |||
| A/C Evap. Temperature Sensor | - | Varies | This displays Counts. This is the evaporator temperature measured in counts. |
| A/C LED | - | Off | The scan tool displays On or Off. This is the state of the air conditioner light emitting diode (LED) indicator. |
| A/C Request | - | No | The scan tool displays Yes or No. Yes is displayed if the air conditioner is requested. |
| Aux. Blower Motor Speed | - | Varies | This displays Counts. This is the auxiliary blower motor speed measured in counts. |
| Aux. Blower Motor Switch | - | Off | The scan tool displays Invalid, Auxiliary, Off, 1, 2 or 3. This is the state of the auxiliary blower motor switch. |
| Aux. Blower Mtr. Spd. Command | - | Varies | This displays Counts. This is the commanded auxiliary blower motor speed measured in counts. |
| Aux. Mode Door Actual | - | Varies | This displays Counts. This is the actual auxiliary mode door position measured in counts. |
| Aux. Mode Door Commanded | - | Varies | This displays Counts. This is the commanded auxiliary mode door position measured in counts. |
| Aux. Temp. Dr. Motor Command | - | Varies | This displays Counts. This is the commanded auxiliary temperature door motor measured in counts. |
| Aux. Temp. Dr. Position | - | Varies | This displays Counts. This is the auxiliary temperature door position measured in counts. |
| Blower Motor Switch | - | Off | The scan tool displays Off, On, High or Invalid. This is the state of the blower motor switch. |
| Defrost Door Actual | - | Varies | This displays Counts. This is the actual defrost door position measured in counts. |
| Defrost Door Commanded | - | Varies | This displays Counts. This is the commanded defrost door position measured in counts. |
| Driver Heated Seat Status | - | Off | The scan tool displays High, Low or Off. This is the state of the driver heated seat. |
| Driver Temp. Dr. Motor Command | - | Varies | This displays Counts. This is the commanded driver temperature door motor measured in counts. |
| Driver Temp. Dr. Position | - | Varies | This displays Counts. This is the driver temperature door position measured in counts. |
| Ignition Voltage Signal | - | Varies | This displays Volts. This is the current ignition voltage signal. |
| Mode Door Commanded | - | Varies | This displays Counts. This is the commanded mode door position measured in counts. |
| Mode Door Position | - | Varies | This displays Counts. This is the current mode door position measured in counts. |
| Mode Status | - | Varies | The scan tool displays Invalid, Vent, Mix-Blend, Floor, Bi-Level, Defrost or Recirc. This is the mode status. |
| Passenger Heated Seat Status | - | Off | The scan tool displays High, Low or Off. This is the state of the passenger heated seat. |
| Psgr. Temp. Dr. Motor Command | - | Varies | This displays Counts. This is the commanded passenger temperature door motor measured in counts. |
| Psgr. Temp. Dr. Position | - | Varies | This displays Counts. This is the current passenger temperature door position measured in counts. |
| Rear Defrost LED | - | Off | The scan tool displays On or Off. This is the state of the rear defrost indicator. |
| Recirculation Dr. Motor Command | - | Varies | This displays Counts. This is the commanded recirculation door motor measured in counts. |
| Recirculation Dr. Position | - | Varies | This displays Counts. This is the recirculation door position measured in counts. |
HVAC Control Module Scan Tool Output Controls
| Output Control | Description |
|---|---|
| A/C Request | The HVAC control module sends out a A/C request signal to turn on the A/C compressor when you select ON. The request signal should stay active until commanded OFF. |
| All Status LEDs | The scan tool displays Commanded State: On or Off. This function commands all LEDs On or Off. |
| Auxiliary Air Temp. Door | The HVAC control module commands the auxiliary air temperature actuator towards 255 counts when you select ON. The HVAC control module commands the auxiliary air temperature actuator towards 0 counts when commanded OFF. |
| Auxiliary Blower Motor | This functions commands Auxiliary Blower Motor On or Off. |
| Auxiliary Mode Door | The HVAC control module commands the auxiliary Mode actuator towards 255 counts when you select ON. The HVAC control module commands the auxiliary Mode actuator towards 0 counts when commanded OFF. |
| Defrost Mode | The HVAC control module commands the Defrost actuator towards 255 counts when you select ON. The HVAC control module commands the Defrost actuator towards 0 counts when commanded OFF. |
| Left Temp. Door Position | The HVAC control module commands the left air temperature actuator towards 255 counts when you select ON. The HVAC control module commands the left air temperature actuator towards 0 counts when commanded OFF. |
| Mode Door Position | The HVAC control module commands the Mode actuator towards 255 counts when you select ON. The HVAC control module commands the Mode actuator towards 0 counts when commanded OFF. |
| Recalibrate All Motors | The scan tool displays Commanded State: None or On. This functions commands all actuators to their fully opened and fully closed positions, and relearns these endpoints. |
| Recirculation Door | The HVAC control module commands the recirculation actuator towards 0 counts when you select ON. The HVAC control module commands the recirculation actuator towards 255 counts when you select OFF. |
| Right Temp. Door Position | The HVAC control module commands the right air temperature actuator towards 255 counts when you select ON. The HVAC control module commands the right air temperature actuator towards 0 counts when commanded OFF. |
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.