Abstract: A control apparatus for an internal combustion engine can detect a tubing disconnection failure of an intake pressure sensor thereby to make it possible to give a warning to a user and to take appropriate measures to cope with such a failure situation. A control unit controls the engine based on a throttle opening, an intake pressure measured by an intake pressure sensor, and a rotational speed and a crank angle of the engine. The intake pressure sensor is connected to the intake system through tubing. The control unit includes a failure diagnosis section that detects an abnormality of the intake pressure sensor. The failure diagnosis section detects an open circuit or a short circuit of a signal line between the intake pressure sensor and the control unit based on a change in the intake pressure, and also detects a disconnection failure of the tubing of the intake pressure sensor.

Abstract: A control apparatus for an internal combustion engine can detect a tubing disconnection failure of an intake pressure sensor thereby to make it possible to give a warning to a user and to take appropriate measures to cope with such a failure situation. A control unit controls the engine based on a throttle opening, an intake pressure measured by an intake pressure sensor, and a rotational speed and a crank angle of the engine. The intake pressure sensor is connected to the intake system through tubing. The control unit includes a failure diagnosis section that detects an abnormality of the intake pressure sensor. The failure diagnosis section detects an open circuit or a short circuit of a signal line between the intake pressure sensor and the control unit based on a change in the intake pressure, and also detects a disconnection failure of the tubing of the intake pressure sensor.

Abstract: A failure detecting device is provided, which includes the transistor for driving the excitation coil of the relay connected to the battery, the power supply monitors for monitoring an output of the relay, the EEPROM for storing failure presence or absence information, and the microcomputer for writing the failure presence or absence information in the EEPROM at the time of power OFF, reading the failure presence or absence information from the EEPROM at the time of power ON, and judging a failure state based on a voltage value detected by the power supply monitor in the case in which a failure is present.

Abstract: A failure detecting device is provided, which includes the transistor for driving the excitation coil of the relay connected to the battery, the power supply monitors for monitoring an output of the relay, the EEPROM for storing failure presence or absence information, and the microcomputer for writing the failure presence or absence information in the EEPROM at the time of power OFF, reading the failure presence or absence information from the EEPROM at the time of power ON, and judging a failure state based on a voltage value detected by the power supply monitor in the case in which a failure is present.