How to Fix Them

3 Common Issues in Car Air Conditioning Systems and How to Fix Them

• Air Not Cold
  Cause: Inadequate refrigerant or equipment leakage.
  Solution: Check for leaks and replace faulty components immediately.
• Intermittently Cold Air
  Cause: Accumulated moisture causing the expansion valve to freeze.
  Solution: Replace the expansion valve, receiver dryer, and flush the system.
• Delayed Cooling
  Cause: Compressor failure resulting in insufficient compression.
  Solution: Replace the compressor, expansion valve, and receiver dryer, then flush the system.
• Weak Cooling
  Cause: Overly pressurized system due to excess refrigerant or poor heat dissipation from condenser.
  Solution: Inspect the radiator fan, check for condenser blockage, verify refrigerant levels, and examine the pressure switch. Address issues as needed.
• Warm Air at the Evaporator Exit
  Cause: Frozen evaporator exit pipe reaching the compressor or excessive expansion valve opening.
  Solution: Quickly release refrigerant to remove excess, and examine the valve. If it’s a blockage issue, replace the expansion valve and flush the system.”

     2. Loud Noise

• Sound Coming from the Passenger Compartment Air Conditioning System
  Cause: This sound often originates from the air conditioning blower motor, which is responsible for blowing cold air from the air vents, or from the valve that injects refrigerant.
  Solution: Adjust the air conditioner settings or fan speed. Observe if the sound level changes. If the sound becomes quieter or different, it suggests that there may be an issue with the blower motor, which may need to be replaced.
• Sound Originating from the Engine Compartment
  Cause: To determine whether the issue is related to the engine or the air conditioning system, you can turn the car’s air conditioner on and off. If there is no sound when the air conditioner is turned off, it indicates a problem with the air conditioner compressor.
  Solution: Check if the air conditioner compressor is making unusual noises and if it can be repaired. If repairs are not possible, you may need to replace the compressor with a new one.

     3. Unpleasant Odor

• Accumulated Food Residues or Sweat
  Cause: The accumulation of food residues or sweat in the car can lead to unpleasant odors.
  Solution: Regularly clean the car by removing unrelated food items and cleaning the interior surfaces consistently.
• Fungi and Bacteria
  Cause: Accumulated moisture or humidity in the evaporator coil can lead to fungal growth.
  Solution: Perform regular cleaning of the air conditioning system using antibacterial cleaning agents. Also, inspect the cooling unit for any potential leaks that may cause fungal growth.
• Air Filter Damaged or Deteriorated
  Cause: A damaged or deteriorated air filter may accumulate mold and cause unpleasant odors when the air conditioner is in use.
  Solution: Replace the air filter with the appropriate model for your car. It is recommended to change the air filter every year or approximately every 20,000 kilometers, or more frequently depending on driving conditions and usage. For example, if driving on dusty roads, the air filter may become dirty faster and need replacement sooner than usual.

Special thanks for the technical expertise and knowledge from Denso Car Service Partner.
If your car’s air conditioning system has issues, it is advisable to contact a garage or service center for professional assistance in troubleshooting and resolving the problems. Additionally, don’t forget to choose high-quality and reliable products.