What Causes Frequent Cycling of the Car Compressor?
3 Answers
Car compressor frequent cycling is caused by the intervention of the car air conditioning energy-saving mode, excessively high exhaust pressure, excessively low suction pressure, insufficient or excessive refrigerant, and excessively high relay setting limits. Intervention of the car air conditioning energy-saving mode: When the temperature reaches the set target, the compressor is turned off to stop working, achieving energy-saving effects. When the temperature rises away from the set temperature, it restarts. Excessively high exhaust pressure and excessively low suction pressure: Moisture in the system causes pipe blockage and icing. The repair method involves flushing the pipes with high-pressure nitrogen gas, increasing the expansion valve opening to adjust the suction pressure, and increasing the cooling water volume to reduce the exhaust pressure. Insufficient or excessive refrigerant: The amount of refrigerant determines the system pressure. Abnormal pressure can cause the compressor to cycle frequently. Excessively high relay setting limits: Appropriately increase the limit value of the high-pressure relay and decrease the limit value of the low-pressure relay. Solutions for frequent cycling of the car compressor: It is necessary to promptly go to the local 4S store for inspection and repair.
Compressor frequent cycling can range from minor to serious. Last time I encountered this on the highway, I almost overheated. The most common issue is refrigerant problems - if there's a leak causing insufficient pressure, the compressor will repeatedly start to compensate. Electrical issues are also common, such as a faulty thermostat or poor wiring contact, causing the compressor to misjudge cabin temperature and cycle on/off constantly. Poor heat dissipation is another factor - if the condenser is blocked by leaves or the fan fails, the compressor may be forced to shut down for protection. Worn electromagnetic clutch causing slippage can also lead to repeated restarts when the compressor can't turn. Finally, don't forget to check voltage - unstable alternator output causing voltage fluctuations can make the compressor control module act erratically. When this happens, it's best to turn off the AC immediately and have a professional shop diagnose the specific cause.
As a car enthusiast, I pay special attention to the air conditioning system. Frequent cycling of the compressor is mostly caused by abnormal system pressure—either too much or too little refrigerant in the AC lines can trigger the protection mechanism. A malfunctioning temperature sensor is also a common issue; if it misreads the cabin temperature, it will incorrectly command the compressor. Heat dissipation system failures are worth noting, such as a dirty condenser in front of the radiator or insufficient cooling fan speed, which can cause the compressor to shut down automatically due to inadequate heat dissipation. Also, don’t overlook oxidized electrical connectors, especially in humid areas where rusted plugs can lead to poor contact, causing intermittent compressor operation. It’s advisable to have the technician check the AC high and low pressure readings during every maintenance service.
