Why is there a buzzing sound from the electric motor in the right rear wheel after turning off the engine?
1 Answers
This situation is normal. It is the sound of the exhaust pipe contracting, and the noise will disappear after a few minutes. Models equipped with electronic parking brakes may also experience this phenomenon, which is the sound of the electronic parking brake motor and is also normal. Here is some extended information: 1. Working principle: The electronic parking brake is a technology that achieves parking braking through electronic control. Its working principle is the same as that of a mechanical handbrake, both achieving parking braking through the friction generated between the brake disc and brake pads. The only difference is that the control method has changed from the previous mechanical handbrake lever to an electronic button. 2. Thermal expansion and contraction of the car exhaust pipe: When the car is running, it burns gasoline, and through complex chemical reactions, part of the energy is converted into heat energy, which is discharged through the exhaust system. The muffler is basically at the end of this system and its function is to reduce the noise of the exhaust. The muffler has to withstand the impact of hot airflow when working, so it naturally heats up. After turning off the engine, due to thermal expansion and contraction, it will make a whirring sound for a while, sometimes quite loud, which is all normal.
