What Causes a Car Air Conditioner to Stop Cooling but Work Again After Restarting?

[SanCora]

There is an issue with the air conditioner's receiver-drier. The car air conditioning system includes a receiver-drier, whose main function is to absorb moisture from the refrigerant and prevent excessive moisture in the refrigerant from reducing cooling capacity. When the desiccant inside the receiver-drier becomes saturated, it can no longer filter out moisture. Methods for maintaining a car air conditioner: 1. Comprehensive inspection of the air conditioner: When using the air conditioner for the first time in summer, inspect the air conditioning system, such as checking the refrigerant and whether the air filter is too dirty through the receiver-drier, and whether there are foreign objects in the radiator. 2. Pay attention to cleaning the air conditioner: Some beginners only think about cleaning the air conditioner when its performance deteriorates, which is incorrect. The air filter should be replaced regularly because Beijing's spring has a lot of sand and flying willow catkins, which can stick to the filter and breed bacteria, causing a musty smell in the air conditioner. Additionally, the condenser should be cleaned periodically, and the radiator should be removed for thorough cleaning. 3. Do not turn off the air conditioner immediately after parking: After reaching their destination, car owners usually turn off the air conditioner and leave immediately. Unlike in autumn and winter, the significant temperature difference between the inside and outside of the car in hot summer can cause the air conditioning system to become moldy and breed mold.

[MacJameson]

That time when I was out driving for fun, the air conditioning suddenly stopped cooling, but it worked fine after a restart, which really puzzled me. Later, when I went for a check-up, I found out it might have been the compressor clutch slipping—basically, when the connection is poor, the current can't pass through, and the compressor doesn't work, but restarting the power can reset the connection. Or it could be that the refrigerant pressure was too high, triggering an automatic shutdown for protection, and the system returned to normal after a restart. Another possibility is an aging relay with unstable contacts—just replacing it with a new one would fix it. Occasionally, the electronic control module might falsely report an error, and restarting is like resetting a computer. I recommend checking the fuse box when parked to see if the fuses for the headlights and air conditioning are loose. If this happens frequently, it's best to go to a shop to test the pressure or replace parts. Otherwise, driving in summer without AC can be unbearable, affecting comfort and causing distractions.

[Zara]

I've been driving for decades and encountered many such air conditioning issues. Common problems are minor electrical faults, such as carbon buildup on relay contacts causing poor connection, or the compressor clutch gap being too large, leading to malfunction during thermal expansion and contraction. Restarting the car resets the power, allowing it to work normally again. It could also be unstable pressure in the refrigerant circulation system, causing the sensor to misjudge and shut down. I don't understand advanced technology, but a simple method is to start with the fuses—check if any are blown and try replacing one. If the issue occurs frequently, it might indicate a component is failing and should be repaired early to avoid trouble on the road. The air conditioning affects driving comfort and safety, so don't neglect maintenance when it's working fine.

[AlyssaAnn]

When I take my child out, the air conditioner sometimes blows hot air, but it works fine after a restart. This could be a temporary shutdown caused by a sensor malfunction or control panel error. Restarting is equivalent to resetting the program. It could also be due to frozen pipes blocking the airflow, which cools down again after thawing. Checking isn't difficult—first, see if the fan is spinning, then feel if the compressor is running. If there's an issue, get it serviced promptly, keep the filter clean to improve efficiency. For safety, don't delay.