Important: The following steps must be completed before using the symptom tables.
- Perform the
Diagnostic System Check - HVAC Systems - Automatic
before using the Symptom Tables in
order to verify that all of the following are true:
• | The control module(s) can communicate via the serial data link. |
- Review the system operation in order to familiarize yourself with
the system functions. Refer to
Visual/Physical Inspection
• | 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 following could cause window fogging: |
- | 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 Wiring Systems.
Symptom List
Refer to a symptom diagnostic procedure from the following list in order
to diagnose the symptom: