What Are the Symptoms of a Faulty Car Air Conditioning Controller?
2 Answers
Phenomena of a faulty car air conditioning temperature control switch: When the engine coolant reaches the set temperature and the electric fan should start, the electric fan does not work; when the engine coolant has not reached the set temperature and the electric fan should not start, the electric fan turns on and keeps working until the battery is drained. Below are the functions of car air conditioning: 1. Temperature regulation: This is the main function of car air conditioning. In summer, the cooling system produces cold air to lower the temperature inside the car; in winter, except for large commercial vehicles that use independent combustion heaters for heating, other vehicles basically utilize the car's residual heat for heating. 2. Humidity regulation: Humidity greatly affects the comfort of passengers inside the car. The humidity inside the car should generally be maintained between 30% and 70%. Ordinary car air conditioning systems do not have the function to regulate humidity inside the car; this can only be achieved by using ventilation devices or advanced luxury cars equipped with integrated heating and cooling air conditioning systems. 3. Airflow regulation: The speed and direction of airflow significantly impact human comfort. If the air blows directly, the speed should be limited to a certain range when the temperature is appropriate. The speed can be adjusted appropriately based on passengers' living environment, age, health condition, and habits regarding cold and heat. 4. Air purification: The quality of air inside the car is an important guarantee of comfort.
I've been driving for nearly twenty years, and the symptoms of a faulty air conditioning controller are numerous. The buttons often malfunction; pressing the fan speed button gets no response, leaving it stuck at either high or low speed, which is noisy and fuel-consuming. Temperature control is also problematic—set to the lowest, yet it blows hot air, turning the car into a sauna in summer. Mode switching is worse, with defrosting failing entirely, making winter fog on the windshield dangerously obstructive. Sometimes the AC turns on/off by itself or refuses to start, requiring repeated attempts. The display may flicker or go blank, with internal short circuits draining the battery. Get it fixed at a repair shop immediately upon noticing these issues—delaying risks both safety and fuel costs. A broken AC in summer is unbearable; don't endure it without repair.
