Symptom Table

SYMPTOMS - HVAC SYSTEMS - MANUAL

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

Visual/Physical Inspection
• Inspect for aftermarket devices which could affect the operation of the HVAC System. Checking Aftermarket Accessories

• 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.

• 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

Intermittent
Faulty electrical connections or wiring may be the cause of intermittent conditions. Diagnostic Aids

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

• Too Hot in Vehicle

• Too Cold in Vehicle

• Air Delivery Improper

• Air Recirculation Malfunction

• Vacuum Control System Diagnostic Vacuum Control System Diagnostic - HVAC System - Manual

• Leak Testing Leak Testing

• Defrosting Insufficient

• Noise Diagnosis - Blower Motor Noise Diagnosis - Blower Motor

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

• Noise Diagnosis - HVAC Module Noise Diagnosis - HVAC Module

• Odor Diagnosis Odor Diagnosis