The reasons why the car horn suddenly stops working on rainy days are as follows: 1. Contact point erosion: If the horn is pressed for a long time, it can easily cause the horn contacts to erode and create impedance. This weakens the current flowing through the electromagnetic coil, reducing the electromagnetic force and preventing it from attracting the armature to drive the diaphragm to vibrate normally, resulting in a hoarse sound or even no sound at all. However, when the horn is pressed continuously, if a strong instantaneous current passes through the impedance, it can still work normally, leading to intermittent functionality. 2. Poor sealing leading to moisture: Although the horn is internally sealed, if the sealing is not tight, moisture can enter during car washing or water vapor can be present in the internal space. This moisture can easily cause the contacts to become damp and fail to function properly. 3. Poor contact at the electromagnetic coil terminals: Some horns have electromagnetic coil terminals with enameled wire connections that are crimped with aluminum rivets instead of being securely welded. If the insulation paint on the enameled wire ends is not properly removed or the rivet crimping is not secure, it can easily lead to a loose connection, causing the horn to malfunction. This type of fault is due to the quality of the horn and cannot be repaired; only a replacement will suffice.
