ELECTRONIC CONTROL DEVICE

PROBLEM TO BE SOLVED: To suppress a force in an abrupt acceleration direction from being applied on a vehicle when torque is increased by turning off a throttle motor.SOLUTION: An electronic throttle which is controlled by this electronic control device fixes an opening of a throttle valve by an energization force of a spring to a predetermined opening necessary for retreat travelling when the throttle motor is turned off. When the motor of the electronic throttle is turned off during the idling of an engine, the throttle valve is opened up to the opening. Therefore, when a failure occurs in electronic throttle control by microcomputer during idling (when a failure in the microcomputer is detected and a throttle change amount at that time is large), a throttle power supply relay circuit for connecting a power supply to the motor is turned off to turn off the motor, and also a fuel cut signal is switched to an on-state, and the transmission of an injector signal is interrupted to cut fuel temporarily. In addition, in a process prior to an end of fuel cut, a fuel cut amount is reduced gradually to suppress a rapid torque increase at the end of the fuel cut.