Too Cold in Vehicle. Saturn L300/LW300 2004

GM Service Manual Online

For 1990-2009 cars only

Makes 🢒 Saturn 🢒 2004 🢒 L300/LW300 🢒 HVAC 🢒 HVAC Systems - Automatic 🢒 Too Cold in Vehicle

Step

Action

Values

Yes

Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

DEFINITION: The temperature cannot be adjusted, or heating is insufficient.

Did you perform the HVAC Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Automatic

Place the blower motor switch in each speed position.

Does the blower motor operate in any speed position?

Go to Step 3

Go to Blower Motor Inoperative

Does the blower motor operate at the desired speeds?

Go to Step 4

Go to Blower Motor Malfunction

Start the engine.
Place the mode switch in the panel position.
Place the recirculation switch in the ON position.
Observe the recirculation door.
Place the recirculation switch in the OFF position.

Does the recirculation door move from the recirculation position to the outside air position?

Go to Step 5

Go to Air Recirculation Malfunction

Does the Too Cold in vehicle condition occur when heating or defrosting is desired?

Go to Step 6

Go to Step 8

Start the engine.
Turn OFF the HVAC controls.

Does the A/C compressor operate?

Go to HVAC Compressor Clutch Does Not Disengage

Go to Step 7

Inspect the cooling system for the following conditions:

•	A low coolant level

•	A loose or worn accessory drive belt

•	A leaking radiator hose or heater hose

•	A kinked radiator hose or heater hose

•	A missing radiator cap pressure seal

•	A leaking radiator cap

Refer to Heating Performance Diagnostic in Heating, Ventilation and Air Conditioning.

Did you find and correct the condition?

Go to Step 23

Go to Step 8

Place the mode switch in panel position.
Turn the ignition ON, with the engine OFF.
Place the blower motor switch in maximum speed position.
Inspect for airflow through the inside air temperature sensor by placing a 5 cm (2 in) square piece of paper over the sensor air inlet.

Does the paper stay in place?

Go to Step 9

Go to Step 15

Install a thermometer near the inside air temperature sensor.
With a scan tool, observe the Inside Air Temp parameter in the General Info-Outputs data list.

Does the scan tool indicate the sensor temperatures is within 3°C (5°F) of the thermometer temperature?

Go to Step 10

Go to Step 13

Turn the ignition OFF.
Cover the ambient light sensor.
Turn the ignition ON.
With a scan tool, observe the Solar Sensor parameter in the Defrost data list.

Is the Solar Sensor parameter greater than the specified value?

220 counts

Go to Step 11

Go to Step 17

Uncover the ambient light sensor.
Direct a light source at the ambient light sensor.
Observe the Solar Sensor parameter in the Defrost data list.

Do the counts change?

Go to Step 12

Go to Step 17

Test the resistance of the ambient air temperature sensor. Refer to Temperature Versus Resistance in Engine Controls - 3.0L or Temperature Versus Resistance in Engine Controls - 2.2L.

Is the resistance near the value in the temperature vs resistance table?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 14

Test the resistance of the inside air temperature sensor. Refer to Temperature Versus Resistance in Engine Controls - 3.0L or Temperature Versus Resistance in Engine Controls - 2.2L.

Is the resistance near the value in the temperature vs resistance table?

Go to Step 18

Go to Step 16

Inspect for poor connections at the harness connector of the ambient air temperature sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 23

Go to Step 21

Inspect the aspirator tube for a air leak or obstruction.

Did you find and correct the condition?

Go to Step 23

Inspect for poor connections at the harness connector of the inside air temperature sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 23

Go to Step 19

Inspect for poor connections at the harness connector of the ambient light sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 23

Go to Step 20

Inspect for poor connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 23

Go to Step 22

Replace the inside air temperature sensor. Refer to HVAC Control Module Replacement .

Did you complete the replacement?

Go to Step 23

Replace the ambient light sensor. Refer to Ambient Light Sensor Replacement in Lighting Systems.

Did you complete the replacement?

Go to Step 23

Replace the ambient air temperature sensor. Refer to Ambient Air Temperature Sensor Replacement .

Did you complete the replacement?

Go to Step 23