Most electric motors have carbon brushes, which are an important component of the motor. They are now used in motor commutators and other areas. They have strong electrical conductivity, thermal conductivity, and lubrication properties, as well as certain mechanical strength and characteristics of commutation sparks. Therefore, with the development of the motor industry, the types of brushes have become increasingly diverse.

However, if there is poor contact with the carbon brushes in automotive electric motors, in fact, as long as the motor brushes are replaced early, the cost is low and the replacement is convenient, it is too late to wait until the commutator is magnetically damaged.

In fact, if there is poor contact, simply wrap 100-grit sandpaper around the copper rectifier, glue it to the joint, press on the motor carbon brush, and within a few minutes, manually rotating the motor will grind it flat to tightly bond with the rectifier.

As long as this method is used to replace the commutator, the problem of poor contact with automotive electric motor carbon brushes will be reduced.