Fault Analysis of Automotive Air Conditioning System

1. Before checking the temperature of the high and low pressure pipes, the air conditioning should be set to the position of maximum cooling, maximum air volume, direct blowing, internal air circulation, and A/C switch on. According to experience, the temperature of the air outlet is around 5 degrees Celsius, which is normal.
2. Raise the engine hood to confirm that the electronic fan is running simultaneously and the compressor is also running. If it is not running, loosen the protective cover of the high-pressure pipe and use a sharp tool to gently press the high-pressure exhaust ejector pin to see if there is a strong refrigerant overflow. If there is, it indicates that the fault of the air conditioning is in the circuit system. If there is no strong leakage of refrigerant, please carefully check the joints of the air conditioning pipe for oil stains. If there are any, it indicates that there is a leakage point in the air conditioning system. This repair may be time-consuming, and it is also possible that one part has been repaired, and there may be other leaks, which is inevitable. Please have a thorough understanding of repairing the leak. Finally, remember to tighten the protective cover.
3. Touch the high-pressure and low-pressure pipes with your hands and carefully feel their temperature. Under the normal operation of the refrigeration system, the normal temperature of the high-pressure pipe is about 50 to 60 degrees Celsius, which means it can be firmly held by hand for about 30 seconds. However long it takes, it cannot be held. The temperature of the low-pressure pipe is approximately between 5 and 6 degrees Celsius, which means you can feel the ice hand with your hand.