Abstract: A control signal generated as a result of the actuation of each of control switches of a control section is multiplexed by a multiplexing section, and the thus multiplexed signal is sent to a multiplex transmission line. Load control sections receive the multiplexed control signal sent over the multiplex transmission line. The load control sections then control the electric power fed to a corresponding one of loads on the basis of the received control signal. Control data, representing the form of output control of the corresponding load which is controlled as a result of the actuation of the control switch, are stored according to the control switches. Control means control the electric power fed to the load on the basis of the control signal using the control data.

Abstract: A switch operating unit 10 has operating switches for operating loads. A load control unit controls the corresponding loads in accordance with the operation of the operating switches according to information, which is stored in first storage device, as to the correlation between the operating switches and the loads. A total rated capacity computation device computes the total rated capacity of the loads to be driven under the control of the load control unit according to information, which is stored in second storage device, as to the rated capacity of each load. When the total rated capacity exceeds a predetermined allowable capacity, the load control unit operates to restrict the driving of the low-priority loads in the order of analog-controlled loads and on-off controlled loads according to the information stored in the second storage device.

Abstract: An input interface using a multiplex type input circuit for selecting a desired one, as its output, of a plurality of input power signals in accordance with a control signal generated by a CPU and for supplying the selected input power signal to an electronic element unit.

Abstract: Disclosed is a corrosion preventing circuit for a switch which, even if a large current switch is used for a small current system such as an electronic unit, can improve long-term durability of the switch in a manner similar to the present level without increasing the burden on the system side, thereby ensuring the reliability of devices belonging to the system. A series circuit consisting of a switching means and a current limiting resistor is connected in parallel to a resistor that is connected in series between a dc power supply and a large current switch. A control circuit turns on the switching means by generating a pulse of a predetermined time width after a predetermined time in accordance with the turning on of the large current switch. The current flowing while the switching means is being turned on is applied to the large current switch, so that an oxide film formed at the contact of the switch is destroyed.