What to Do When the Car Air Conditioning Switch Doesn't Respond?
2 Answers
Possible reasons for sudden car air conditioning failure: 1. Blocked pipelines: causing excessively high pressure or excessively low pressure; 2. Poor heat dissipation; 3. Blocked expansion valve; 4. Insufficient or excessive refrigerant; 5. Compressor not operating. Below are the solutions: 1. Check the refrigerant pressure: If the pressure is too low, the refrigerant is insufficient and needs to be replenished. Insufficient refrigerant will affect the cooling efficiency of the air conditioning. Check whether the blower of the air conditioning system is operating normally and the air volume. If the blower malfunctions, the cold air from the air conditioning system cannot be delivered to the car interior in time, resulting in no cold air from the air vents. 2. Check if the evaporator of the air conditioning system is too dirty: If the evaporator surface is too dirty, the cold air from the air vents will decrease, as the cold air is mainly produced by the evaporator. Check for leaks in the condenser pipelines, as leaks will prevent the air conditioning system from cooling. Inspect the condenser of the air conditioning system to see if its surface is too dirty, as a dirty condenser will affect heat dissipation and thus the operation of the air conditioning system. 3. Refrigerant malfunction: The refrigerant's circulation in the pipelines depends on the compressor's operation. If the compressor cannot engage due to abnormal refrigerant pressure, circuit failure, damaged temperature sensor, or burned-out electromagnetic clutch, cooling will be insufficient. It is recommended to replace the temperature sensor or electromagnetic clutch.
Last time my car's AC switch suddenly stopped working, pressing it had no response at all, and it was unbearably hot in the summer. Check the fuse immediately—it's the most common issue. The fuse box is usually located under the steering wheel or in the engine compartment; refer to the manual to find the fuse related to the AC. If it's blown, replace it with a spare one—that usually fixes the problem. If the fuse is fine, the issue might be poor contact in the switch itself, caused by dust or oxidation blocking the signal. Lightly tapping the switch or cleaning the contacts with a cleaner can sometimes help. Another possibility is a loose wiring connection—like in my case, unplugging and replugging the connector tightly fixed it. However, if there's a short circuit or relay failure, you'll need a multimeter to diagnose it, and it's safer to have a professional handle it. Don’t underestimate this issue—AC failure in hot weather can easily lead to discomfort or distracted driving. It's best to check regularly to avoid trouble.
