What Causes the Abnormal Noise from Mercedes-Benz Air Vents?
2 Answers
Abnormal noise from Mercedes-Benz air vents may be caused by issues such as blower noise, air conditioning compressor problems, or belt friction. Blower Noise: Damaged bearings in the blower can cause squealing or humming sounds. Another possibility is resonance noise caused by foreign objects entering the blower. The same applies to the electric fan. Air Conditioning Compressor: Aging of the air conditioning compressor leads to internal wear, resulting in abnormal noise. Alternatively, insufficient lubrication in the compressor can also cause noise. Weakened Belt Friction: When the air conditioning is turned on, the engine load increases. If the belt's friction weakens, it can produce a sharp, screeching sound.
I've repaired quite a few Mercedes-Benz vehicles before, and air vent noise issues are quite common. Generally speaking, the most common cause is a problem with the fan or blower system. If the blades are unbalanced or contaminated with dust and grease, the fan will produce a buzzing sound when rotating. Foreign objects stuck in the air ducts, such as small leaves or dust particles, can also cause friction noises. Another factor is bearing wear; after several years of use, worn bearings can produce a whining sound. Loose air vent components are also not a minor issue, as they can resonate and create buzzing noises on bumpy roads. I recommend first trying to clean the air vents yourself using a soft brush to remove accumulated dust. If the problem persists after cleaning, take it to a professional shop immediately to check the fan motor and mounting screws—Mercedes' precision systems shouldn't be tampered with casually. Regular air conditioning maintenance can prevent such issues, saving both money and hassle.
