Motor-electric Horn is on a metal diaphragm vibrating sound. Motor-electric horn cores, magnetic coils, contacts, armature, diaphragms, and other components. When the driver presses the Horn switch, current contacts through the coil, coil to produce the magnetic armature under, forcing the diaphragm moves, move the armature Contact disconnect, current disruption, coil magnetic disappears, the diaphragm in its own Flex and spring together with armature reinstated, contact the circuit connected again, have a magnetic current flowing through the coil through the contact points, repeat the above action. Repeat this cycle continuous vibration of the diaphragm, to make sound. Resonance plate and diaphragm of rigid joints, can make the sound more pleasant vibration ride comfort (the electromagnet principle).