For 1990-2009 cars

Important: Review the Air Delivery Description and Operation and the Air Temperature Description and Operation in order to familiarize yourself with the system functions.

### Visual/Physical Inspection

• | Inspect for aftermarket devices which could affect the operation of the system. Refer to Checking Aftermarket Accessories in Wiring Systems.

• | Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

• | Inspect all related ground points for being clean and tight.

### Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

### Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

• | HVAC Compressor Clutch Does Not Engage

• | HVAC Compressor Clutch Does Not Disengage

• | Blower Motor Always On

• | Blower Motor Inoperative

• | Blower Motor Malfunction

• | Air Recirculation Malfunction

Refer to Symptoms - Engine Cooling in Engine Cooling for diagnosis of the electric cooling fans.

Refer to the following in Heating, Ventilation and Air Conditioning:

• | Leak Testing

• | Air Conditioning (A/C) System Performance Test

• | VDOT Air Conditioning (A/C) System Diagnosis

• | Noise Diagnosis - Air Conditioning (A/C) System

• | Odor Diagnosis