- Symptoms - HVAC Systems - Manual

Symptoms - HVAC Systems - Manual

Important: Review the system operation in order to learn the system functions. Refer to the following procedures:


* Air Delivery Description and Operation (Air Delivery Description and Operation)

* Air Temperature Description and Operation (Air Temperature Description and Operation)


Visual/Physical Inspection

* Inspect for aftermarket devices which could affect the operation of the HVAC System. Refer to Checking Aftermarket Accessories (Component Tests and General Diagnostics).
* Inspect the system components which are easily accessible or visible for obvious damage or for 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 (Air Temperature Description and Operation).
* The following conditions may cause window fogging:

- A wet carpet
- High humidity
- An interior water leak
- A blocked drain tube to the A/C evaporator
- Maximum passenger capacity
- Blocked body pressure relief valves

* Inspect the air distribution system for causes of reduced airflow:

- An obstructed or dirty passenger compartment air filter
- Blocked or damaged air vents

Intermittent

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

Symptom List

Refer to one of the following symptom diagnostic procedures:

* Air Conditioning Compressor Malfunction (Air Conditioning Compressor Malfunction)
* Blower Motor Malfunction (Blower Motor Malfunction)
* Air Temperature Malfunction (Air Temperature Malfunction)
* Air Delivery Improper (Air Delivery Improper)
* Air Recirculation Malfunction (Air Recirculation Malfunction)
* Leak Testing (Leak Testing)
* Defrosting Insufficient (Defrosting Insufficient)
* Noise Diagnosis - Blower Motor (Noise Diagnosis - Blower Motor)
* Noise Diagnosis - Air Conditioning (A/C) System (Noise Diagnosis - Air Conditioning (A/C) System)
* Noise Diagnosis - HVAC Module (Noise Diagnosis - HVAC Module)
* Odor Diagnosis (Odor Diagnosis)