Visual/Physical Inspection
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- Inspect for aftermarket devices which could affect the operation of the HVAC 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.
- Verify the A/C compressor clutch turns freely and is not seized.
- Verify that the customer is using the correct key to enable personalization and is not inadvertently activating auxiliary HVAC controls.
- The A/C compressor will not operate in cold outside air temperatures. Refer to AIR TEMPERATURE DESCRIPTION AND OPERATION .
- The following conditions may cause window fogging:
- Wet carpet or mats
- High humidity
- Interior water leak
- Blocked A/C evaporator drain tube
- Maximum passenger capacity
- Blocked body pressure relief valves
- Inspect the air distribution system for causes of reduced air flow:
- Obstructed or dirty passenger compartment air filter, if equipped
- Blocked or damaged air inlet or outlet vents