What Causes Intermittent Cooling in Car Air Conditioning?
3 Answers
Causes of intermittent cooling in car air conditioning are as follows: 1. Observe the engagement of the air conditioning compressor: Check whether the compressor is engaging. Possible reasons for the compressor not engaging, besides the compressor itself, include the powertrain control module (PCM), the request signal from the air conditioning switch, pressure sensor signals, and indoor/outdoor temperature sensors. 2. Overcharging of refrigerant causing system pressure to frequently exceed the normal upper limit: This leads to the air conditioning being cut off due to pressure protection. 3. Poor heat dissipation of the condenser: Resulting in high pressure.
The car air conditioning sometimes works and sometimes doesn't. I've encountered this issue several times. Usually, it's due to insufficient refrigerant or a small leak, causing pressure instability and fluctuations. If the compressor clutch is worn, it slips severely at high temperatures, making the air conditioning turn on and off intermittently, accompanied by a clicking sound. There's also the issue with the temperature sensor misreading the cabin temperature, causing the system to shut down erroneously. Electrical problems like poor fuse contact or relay failure can also cause signal interruptions. I recommend first checking the air conditioning pipes for any oil stains or signs of leakage, and testing the refrigerant pressure. Don't delay; driving in summer without air conditioning is not only uncomfortable but also affects concentration—safety first. Regular checks can avoid major repairs, saving both hassle and money.
Intermittent cooling can be caused by various reasons, such as refrigerant leaks or insufficient levels leading to pressure fluctuations, or when the compressor clutch engages unstably, resulting in intermittent operation. Misjudgment of temperature by controllers or sensors is also common, causing the system to shut down automatically. Don't overlook electrical components; poor relay contact or loose wiring can interrupt signals, and unstable fan speed leading to poor heat dissipation also affects performance. I recommend using diagnostic tools to scan for error codes to identify the specific issue. Regular maintenance, such as cleaning dust from the condenser and evaporator, is crucial, as problems are more likely to surface under heavy system loads. This issue tends to worsen in high-temperature environments, so preventive maintenance is essential to avoid future problems.
