A disk drive system is disclosed that includes a disk device coupled to control circuitry. The new code number itself not only provides the code signature, but it is also used for the OVSF code generation. In addition, a menu is output to independently control an output image of the multimedia system and the portable terminal to the vehicle. The thermoelectric switches operate such that an on state is defined as heat flow being allowed by virtue of the thermal conductivity of the thermoelectric switch. Then, the separation time of the arcing contacts is calculated as the difference between the separation time of the auxiliary contacts measured during the operating condition other than the predefined test condition and the calculated time delay.