Why does the car make noise when the air conditioning is turned on?
2 Answers
When the car's air conditioning is turned on and noise occurs, it usually comes from two sources: one is the sound from the blower inside the car, and the other is the sound from the engine belt or compressor. When there is a problem with the compressor's electromagnetic clutch, it can cause the compressor to make noise. Here are some additional details: 1. Due to the transition from low to high-speed rotation, the requirements for the electromagnetic clutch are very high, and most electromagnetic clutches are installed close to the ground. When the bearings inside the electromagnetic clutch are damaged, it can cause noise. 2. Excessive clearance between the electromagnetic clutch and the compressor, loose drive belt, or low compressor efficiency may reduce power generation, leading to insufficient generator voltage and resulting in abnormal noise. 3. If there are foreign objects or lack of oil inside the blower, or if the blower itself is severely worn, it can also cause abnormal noise. Additionally, if the air filter has not been replaced for a long time, there may be foreign objects in the air ducts that can produce noise.
My old car had the same issue last year, buzzing annoyingly when the AC was turned on. Later, a check revealed it was due to worn-out bearings in the AC compressor, causing imbalance and noise during operation. I also encountered a situation where leaves got tangled in the fan blades, making a whooshing sound like a tractor. I suggest you listen to where the noise is coming from: if it's a clicking sound from the dashboard, it might be a broken gear in the flap motor; a whistling sound from the front is likely abnormal refrigerant flow. Not fixing these parts in time could damage the entire system. I took mine straight to the repair shop for a lift check, and they found a water bottle cap stuck in the blower—removing it made everything quiet again.
