The control logic of automobile in the electrical system is basically the same, the inspection principle is also basically the same and the circuit is tested according to the circuit diagram. The following analysis is done by taking the lighting control system as an example .The vehicle’s lighting lamps are the indispensable lighting equipment during the driving. To increase the driving speed and ensure the driving safety , and the normal operation of the engine , the vehicle is equipped with multiple kinds of lighting equipment and signal devices. The course first introduces the composition, function, structure, and control principle of lighting and signaling devices. Then, it introduces the operation of light switches and checks the working condition of lights. Finally, taking the turn signal control system as an example, it analyzes the maintenance of the turn signal electrical system.