The Driver Guide System fills the much needed function of route guidance in today's society. This system uses terrestrial magnetism to detect the position of an automobile and to guide it to its destination. Differing from other such systems which are under development, this system does not require land installations. At the time of development, the greatest problem was how to control the strong magnetism of body panels and the magnetic field given off by electrical equipment in order to achieve a high degree of accuracy in the detection of subtle terrestrial magnetism. We have developed a highly practical system through the application of a wide range of technology in circuitry and a structure and the effective use of software.