Because, when using the so-called car sunshade, the general vehicle is in a non-working state, and at this time, the electronic components of the vehicle are in a dormant state, and there will be no magnetic field or signal interference. But when using, we must pay attention to the impurities absorbed by the magnet to avoid scratching the paint surface of the car body.
In addition, don't put it too close to the sensor, otherwise it will easily make the sensor abnormal.