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Air Conditioning Trouble Shooting

WARNING: This is GENERAL  information. This article is not intended to be specific to any unique situation or individual vehicle configuration. The purpose of this Trouble Shooting information is to provide a list of common causes to problem symptoms. For model-specific Trouble Shooting, refer to SUBJECT, DIAGNOSTIC, or TESTING articles available in the section(s) you are accessing.
BASIC AIR CONDITIONING TROUBLE SHOOTING CHART

CONDITION POSSIBLE CAUSE
Compressor Not Working Compressor clutch circuit open.
..... Compressor clutch coil inoperative.
..... Poor clutch ground connection.
..... Fan belts loose.
..... Thermostatic switch inoperative.
..... Thermostatic switch not adjusted.
..... Ambient temperature switch open.
..... Superheat fuse blown.
Excessive Noise or Vibration Missing or loose mounting bolts.
..... Bad idler pulley bearings.
..... Fan belts not tightened correctly.
..... Compressor clutch contacting body.
..... Excessive system pressure.
..... Compressor oil level low.
..... Damaged clutch bearings.
..... Damaged reed valves.
..... Damaged compressor.
Insufficient or No Cooling; Compressor Working Expansion valve inoperative.
..... Heater control valve stuck open.
..... Low system pressure.
..... Blocked condenser fins.
..... Blocked evaporator fins.
..... Vacuum system leak.
..... Vacuum motors inoperative.
..... Control cables improperly adjusted.
..... Restricted air inlet.
..... Mode doors binding.
..... Blower motor inoperative.
..... Temperature above system capacity.