What are the reasons for the car air conditioner not starting in cold weather?
2 Answers
The reasons why the car air conditioner does not start in cold weather are as follows: Severe internal wear of the compressor: This makes it impossible for the compressor to function normally. The compressor plays a crucial role in the air conditioning system, as its main job is to compress and deliver the refrigerant. This causes the compressor to operate at high speeds for extended periods, which is one of the reasons it may fail to work properly. Refrigerant leakage: The compressor is primarily used to compress and deliver the refrigerant. If there is an issue, check for any refrigerant leaks. Without refrigerant to compress or deliver, the compressor naturally will not work. Electrical system failure: This can effectively prevent the car air conditioner compressor from functioning properly. If this is the case, the owner should check the circuit for continuity and inspect the temperature sensor and solenoid valve.
The phenomenon of car air conditioning not starting in cold weather is common in many models, especially after a sudden temperature drop. From my frequent repair experience, the main cause is abnormal operation or incorrect settings of the ambient temperature sensor – when the sensor detects the outside temperature below a certain point (usually around 5 degrees), the system automatically disables the compressor to prevent condenser icing damage. Battery issues are another factor; voltage fluctuations in cold weather may lead to insufficient power to start the AC motor, particularly in older vehicles. Don’t overlook refrigerant pressure control: increased refrigerant viscosity in low temperatures can cause pressure sensors to misread data, prompting the control module to prevent compressor operation. I recommend starting the engine to warm it up for a few minutes before trying the AC button again. If it still doesn’t work, it’s best to visit a professional shop to inspect the sensors and control unit—avoid disassembling components randomly to prevent wiring damage. Additionally, develop routine maintenance habits, such as checking the AC system’s sealing before winter, to avoid bigger issues.
