Orlando

Air Temperature Malfunction

With the temperature switch at the HVAC controls, the desired air temperature flap position can be put in. The selected value is passed to the HVAC control module via the LIN-Bus. The HVAC control module supplies a 12 V reference voltage to the stepper motor and energizes the 4 stepper motor coils with a pulsed ground signal. The stepper motor puts the mixed air flap into the calculated position, in order to reach the selected temperature.

Check the following mechanical fault sources:

Schematic Reference

HVAC Schematics : Automatic

Connector End View Reference

Component Connector End Views

Description and Operation

Automatic HVAC Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, measure actual inside air temperature using a thermometer. Compare this value to the scan tool Passenger Compartment Air Temperature parameter. The measured temperature should be within 5°C (9°F) difference of parameter value.

⇒	If not within the specified range

Refer to DTC B0163 or B0183 .

⇓	If within the specified range

2. Measure actual temperature using a thermometer at each of the duct temperature sensors. Compare this value to the appropriate scan tool Duct Actual parameter. The measured temperature should be within 5°C (9°F) difference of appropriate Duct Actual parameter value.

⇒	If not within the specified range

Refer to DTC B0173, B0178, or B3933 .

⇓	If within the specified range

3. Measure actual evaporator temperature using a thermometer. Compare this value to the scan tool A/C Evaporator Temperature Sensor parameter. The measured temperature should be within 5°C (9°F) difference of parameter value.

⇒	If not within the specified range

Refer to DTC B0173, B0178, or B3933 .

⇓	If within the specified range

4. Observe the scan tool Sunload parameter. The reading should be between 50-1 150 W/m² and change with sunlight intensity.

⇒	If not within the specified range

Refer to DTC B0163 or B0183 .

⇓	If within the specified range

5. Engine is running, activate and deactivate the A/C switch. Verify the A/C compressor can be activated and deactivated.

⇒	If the A/C compressor cannot be activated or deactivated

Refer to Air Conditioning Compressor Malfunction .

⇓	If the A/C compressor can be activated and deactivated

6. Verify the engine reaches its operating temperature.

1. Ignition ON, turn the temperature knob in all positions. Verify the scan tool Left Temperature Knob Position parameter. The reading should be between -5 to +5 and change with the knob position. At the left end position the reading should be 18 and at the right end position -18.

⇒	If not the specified value

Replace the A26 HVAC Controls.

⇓	If the specified value

2. Replace the M6L Air Temperature Door Actuator - Left and verify the M6L Air Temperature Door Actuator - Left can be put into all positions.

⇒	If the M6L Air Temperature Door Actuator - Left cannot be put into all positions

Replace the K33 HVAC Control Module.

⇓	If the M6L Air Temperature Door Actuator - Left can be put into all positions

3. All OK.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.