Air Conditioning System Faults

This section covers mechanical and possible fuse faults that could occur in the air conditioning system. Visual checks of components within the system and relevant fuses should be carried out before undertaking detailed fault diagnosis procedures on Testbook.

For details of possible faults to vent flap servo motors that are common to heating, ventilation and air conditioning Systems. See HEATING AND VENTILATION Fault diagnosis. Heating and Ventilation Fault Diagnosis

Symptom - Condenser Fan Motor Inoperative or Slow Running.

POSSIBLE CAUSE
^ Blown fuse.
REMEDY
^ Check and renew fuse 34.
POSSIBLE CAUSE
^ Loose electrical connections.
REMEDY
^ Check and tighten all relevant connections.
POSSIBLE CAUSE
^ Worn internal motor components.
REMEDY
^ Renew fan motor.

Symptom - Condenser Fan Motor and/or Condenser Vibration.

POSSIBLE CAUSE
^ Fan motor and/or blades out of alignment.
REMEDY
^ Check for visual damage.
POSSIBLE CAUSE
^ Fan motor/s out of balance.
REMEDY
^ Balance fan motors.
POSSIBLE CAUSE
^ Build up of debris on tan blades.
REMEDY
^ Clean blades with a suitable non-inflammable cleaner.
POSSIBLE CAUSE
^ Excessive wear of fan motor bearings.
REMEDY
^ Renew condenser fan and motor assembly.
POSSIBLE CAUSE
^ Condenser unit not mounted securely.
REMEDY
^ Secure as necessary.

Symptom - Compressor Clutch Inoperative

POSSIBLE CAUSE
^ Blown air conditioning system fuse.
REMEDY
^ Check and renew fuse 8 or 17.
POSSIBLE CAUSE
^ Loose electrical connections.
REMEDY
^ Check and tighten all electrical connections.
POSSIBLE CAUSE
^ Defective electrical or mechanical components.
REMEDY
^ Renew compressor.
POSSIBLE CAUSE
^ Refrigerant circuit problem.
REMEDY
^ Check and rectify.

Symptom - Compressor Clutch Noisy

POSSIBLE CAUSE
^ Loose drive belt.
REMEDY
^ Check drive belt tensioner or renew drive belt.
POSSIBLE CAUSE
^ Compressor not mounted securely.
REMEDY
^ Secure as necessary.
POSSIBLE CAUSE
^ Bearing in clutch pulley not pressed in.
REMEDY
^ Renew compressor.
POSSIBLE CAUSE
^ Clutch will not spin freely.
REMEDY
^ Renew compressor.
POSSIBLE CAUSE
^ Oil on clutch face.
REMEDY
^ Check compressor seals for leaks; if apparent, renew compressor.
POSSIBLE CAUSE
^ Slipping clutch.
REMEDY
^ Renew compressor.
POSSIBLE CAUSE
^ Compressor pump seizing.
REMEDY
^ Renew compressor.
POSSIBLE CAUSE
^ Icing.
REMEDY
^ Check for suction line frosting. Renew expansion valve or receiver/drier, if necessary.

Symptom - Blower Motors Inoperative or Slow Running.

POSSIBLE CAUSE
^ Blown fuse.
REMEDY
^ Check and renew fuse 42 or 43.
POSSIBLE CAUSE
^ Loose electrical connections.
REMEDY
^ Check and tighten all relevant connections.
POSSIBLE CAUSE
^ Worn internal motor components.
REMEDY
^ Renew blower motor/s.

Symptom Blower Motor vibration

POSSIBLE CAUSE
^ Blower motor/fan out of alignment.
REMEDY
^ Check for visual damage.
POSSIBLE CAUSE
^ Blower motor/s out of balance.
REMEDY
^ Balance or renew motor/fan assembly.
POSSIBLE CAUSE
^ Excessive wear of motor bearings.
REMEDY
^ Renew motor/fan assembly.
POSSIBLE CAUSE
^ Blower motor not mounted securely.
REMEDY
^ Secure as necessary.

Symptom - Air conditioning system inoperative

POSSIBLE CAUSE
^ Blown air conditioning system fuse.
REMEDY
^ Check and renew fuses 8 or 17.
POSSIBLE CAUSE
^ Switch control panel/ ECU faulty.
REMEDY
^ Check and renew fuse 8 or fit new switch control panel.