Diagnostic Routine G

Diagnostic Routine G

Diagnostic Overview

Climate Control System Functional Test

Normal Operation and Fault Conditions

This pinpoint test tests the functions of the HVAC (Heating, Ventilation, and Air Conditioning) system and identifies the correct HVAC (Heating, Ventilation, and Air Conditioning) symptom pinpoint test.

Pinpoint Test

1. PERFORM A SELF-TEST ON THE PCM (Powertrain Control Module) AND HVAC (Heating, Ventilation, and Air Conditioning) MODULE

1. Ignition ON.

2. Using a scan tool, perform PCM (Powertrain Control Module) and HVAC (Heating, Ventilation, and Air Conditioning) module self-tests.

Are any climate control related DTCs (Diagnostic Trouble Codes) present?








2. CHECK THE BLOWER MOTOR OPERATION

1. Ignition ON.

2. Select panel mode.

3. Observe blower motor operation and select each blower motor speed.

Does the blower motor operate in all selections and change speed in each?








3. CHECK AIRFLOW OPERATION

1. Select the highest blower motor setting.

2. NOTE: REFER to System Operation for correct airflow descriptions.
While observing the airflow, select each of the airflow positions (panel, panel/floor, floor, floor/defrost, defrost).

Is the airflow directed to the correct outlets?








4. CHECK THE RECIRCULATION OPERATION

1. With the engine running, press the recirculation button (indicator off).

2. Select panel mode.

3. Select the highest blower motor setting.

4. Observe airflow noise.

5. Press the recirculation button (indicator on).

Does the airflow noise increase when the recirculation mode is selected (indicator on)?








5. VERIFY TEMPERATURE CONTROL OPERATION

1. Start the vehicle and allow it to reach normal operating temperature.

2. With the A/C (Air Conditioning) off, select panel mode.

3. Change the temperature setting from the coldest to the warmest and back to the coldest.

Does the temperature change between very warm to cool?








6. VERIFY THE A/C (Air Conditioning) CLUTCH DOES NOT ENGAGE WITH A/C (Air Conditioning) OFF

1. With the engine running and the A/C (Air Conditioning) off, select panel mode.

2. Select the coldest temperature setting.

Is the outlet temperature close to ambient temperature?








7. VERIFY A/C (Air Conditioning) CLUTCH ENGAGEMENT IN THE A/C (Air Conditioning) MODE

1. Make sure the ambient air temperature is above 2 C (36 F).

2. With the engine running, select panel mode.

3. Press the A/C (Air Conditioning) button (indicator on).

Does the A/C (Air Conditioning) clutch engage when the panel and A/C (Air Conditioning) button (indicator on) is pressed?








8. CHECK FOR INSUFFICIENT COOLING

1. Change the temperature setting to coldest (MAX A/C).

2. Press the A/C button if the indicator is not on.

Does the Air Conditioning (A/C) compressor clutch engage and cycle on/off when the A/C indicator is on?