The loudspeaker is relatively high in frequency, but sometimes the sound of the horn of the car sometimes sounds like a mosquito; sometimes it doesn't sound; sometimes it seems hoarse as if it were ill. But most of the owners of the car are directly sent to the car repair shop to go to Victoria. Let's first look at how speakers work. When the horn button on the steering wheel or other position is pressed, the current from the battery will flow through the loop to the electromagnetic coil of the horn relay. The electromagnetic coil draws the movable contact switch of the relay to close, and the current will flow to the horn. The current makes the electromagnet inside the loudspeaker work, so that the vibrating membrane vibrate and make the sound. According to the author's experience, in many faults related to loudspeakers, the problem of speakers is often the failure of speakers themselves. In particular, there are some defects in the location of loudspeakers installed in some automobiles. When it rains, the loudspeakers are easily drenched by rain, resulting in the damage of loudspeakers. When the horn does not sound, the common fault location is not more than 3 points, that is, the horn itself, the horn switch contact and the horn harness. When the failure occurs, it can be checked by the following steps. 1. sometimes do not sound: press the horn switch, if the horn sometimes ringing, sometimes does not sound, most of the horn switch internal contact is not good, some of the horn itself is a problem. 3. no sound at all: first check the fuse to see if it is blown, then pull off the horn plug, and use multimeter to measure whether there is electricity in the horn switch. If there is no electricity, check the horn harness and the horn relay. If there is electricity, it is the problem of the horn itself. At this time, you can also try to adjust the adjusting nut on the horn to see if it can sound. If it doesn't sound, you need to change the horn. 2. hoarse voice: mostly due to poor contact of the plug, especially the various contact points around the steering wheel, because of frequent use, easy to make contact wear. If you have a better way to interact with us on our Chinese used car city WeChat platform, we will give you information about car maintenance and maintenance every day, if you have a better way to interact with us on our Chinese used car city WeChat platform.