Abstract: An ECU is equipped with an engine control microcomputer for executing engine control and a throttle control microcomputer for executing throttle control. The engine control microcomputer is programmed to execute a monitor program. A time in the engine control microcomputer is set with a predetermined time each time the monitor program is executed normally. The timer switches automatically its output logic level at a port from high to low, when the time count reaches zero. When the output logic level is switched to low, a throttle motor is disabled.

Abstract: An ECU is equipped with engine control microcomputer for executing engine control and a throttle control microcomputer for executing throttle control. The engine control microcomputer is programmed to execute a monitor program. A timer equipped in the engine control microcomputer is set with a predetermined time each time when the monitor program is executed normally. The timer switches automatically its output logic level of a port from high to low, when the time count reaches zero.

Abstract: A monitoring process of a subordinate CPU executes a monitoring subroutine based on external data to check if a main CPU is operating properly or not. A ROM stores test input data for the monitoring subroutine and reference data that should be obtained by the monitoring subroutine based on the test input data. The subordinate CPU alternately executes the monitoring process and a logic determination process which executes the monitoring subroutine based on the test input data. When the monitoring subroutine gives results different from the reference data, the logic determination process determines that there is an abnormality in the monitoring subroutine.

Abstract: A control system has a plurality of processors connected in a series order. Each of the processors monitors a preceding processor for operating abnormalities. If an abnormality is detected the operation of abnormal preceding processor is terminated and a resetting unit resets the abnormal processor along with any preceding processor to the abnormal processor in the series order. The system also includes failsafe mechanisms to insure failsafe operation of the vehicle when the operation of an abnormal processor is terminated.

Abstract: An anti-theft system is arranged so that an operation of an engine of a vehicle is maintained as it is even when a CPU of an engine control unit is reset for some reason during when the engine is operative. A CPU of a security ECU performs arithmetic operations for enabling or inhibiting injection of fuel to the engine and for enabling to start a starter on condition that a door key switch and an ignition switch are both turned on. The CPU of the engine ECU performs arithmetic operations to maintain the injection of fuel to the engine based on data of fuel injection enabling or inhibiting process stored in a B/U RAM even when it is reset after receiving the data of process for enabling or inhibiting the injection of fuel from the CPU.

Abstract: An anti-theft system is arranged so that an operation of an engine of a vehicle is maintained as it is even when a CPU of an engine control unit is reset for some reason during when the engine is operative. A CPU of a security ECU performs arithmetic operations for enabling or inhibiting injection of fuel to the engine and for enabling to start a starter on condition that a door key switch and an ignition switch are both turned on. The CPU of the engine ECU performs arithmetic operations to maintain the injection of fuel to the engine based on data of fuel injection enabling or inhibiting process stored in a B/U RAM even when it is reset after receiving the data of process for enabling or inhibiting the injection of fuel from the CPU.

Abstract: A throttle control CPU drives an electric motor throttle valve control based on an accelerator position. When detecting an abnormality in the throttle opening control system, a main CPU stops driving the electric motor and controls fuel injection amount and/or ignition timing to curb engine output torque increases otherwise caused by a valve opening movement (performed until a cooperative member connected to the throttle valve contacts a restricting member mechanically connected to the accelerator pedal). Thereafter, opening of the throttle valve is regulated according to the accelerator pedal position while the restricting member and the cooperative member remain in contact. The control apparatus smoothly shifts the throttle opening regulation to the fail-safe mode when an abnormality occurs by actively controlling engine speed changes during mode transition.