The reference book contains information on the principles of operation, design and characteristics of automotive sensors (control devices and emergency alarms, engine and car control systems), electronic and electromagnetic relays, switches, relay units and fuses. The book contains data on domestic cars manufactured by VAZ, GAZ and AZLK, including modern LADA KALINA, VOLGA GAZ-31105 and GAZEL with anti-lock brakes (ABS). Practical recommendations for diagnosing and troubleshooting the listed devices of the electrical equipment of cars are presented. The reference book is intended for car owners, as well as for service station employees.