- Symptoms - HVAC Systems - Manual

Symptoms - HVAC Systems - Manual

Important: Review the system operation in order to familiarize yourself with the system functions. Refer to the following procedures:

* Air Delivery Description and Operation

* Air Temperature Description and Operation

Visual/Physical Inspection

* Inspect for aftermarket devices which could affect the operation of the HVAC System.
* 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.
* The A/C compressor will not operate in cold outside air temperatures. Refer to Air Temperature Description and Operation.
* The following could 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

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Symptom List

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

* Air Conditioning Compressor Malfunction
* Blower Motor Malfunction
* Too Hot in Vehicle
* Too Cold in Vehicle
* Air Delivery Improper
* Leak Testing
* Defrosting Insufficient
* Noise Diagnosis - HVAC Module
* Odor Diagnosis