Manual Climate Control

1. Verify the customer concern by operating the climate control system.
2. Visually inspect for obvious signs of mechanical and electrical damage; refer to the visual inspection chart:

VISUAL INSPECTION CHART

Mechanical
^ Drive belt
^ A/C clutch
^ Vacuum lines
^ Discharged A/C system
^ Refrigerant lines
^ Vacuum control motor

Electrical
^ Fuse
^ Blower motor
^ A/C compressor
^ Cooling fan
^ Circuit
^ A/C control
^ Electrical connectors

NOTE:
^ To prevent a situation where defrost cannot he obtained, the air handling system is designed to provide defrost when no vacuum is applied to any of the three vacuum control motors. A leak in the vacuum control circuit will send all airflow to the defroster outlets. This condition may occur during acceleration (slow leak), may exist at all times (large leak), and may exist only when specific functions are selected (indicating a leak in that portion of the circuit).
^ The vacuum hoses used in the passenger compartment control circuit are constructed from PVC plastic material. The vacuum hoses used in the engine compartment are constructed of Hytrel. Because of the materials used, the vacuum hoses should never be pinched off during diagnosis to locate a leak.

3. If the fault is not visually evident, determine the symptom and proceed to the Symptom Chart. Symptom Related Diagnostic Procedures