Abstract: A failure diagnosis apparatus for a vehicle is disclosed. The apparatus includes a diagnosis processing section for executing failure diagnosis processing on a device of the vehicle to generate a diagnosis result. The apparatus also includes a data managing section for managing data of the diagnosis result. After an execution condition is met for failure diagnosis, the diagnosis processing section outputs an execution demand to the data managing section for the failure diagnosis processing. In response to the execution demand, the data managing section outputs an execution permission to the diagnosis processing section for the failure diagnosis processing. Also, after the execution condition is met for the failure diagnosis, the diagnosis processing section starts executing the failure diagnosis processing regardless of whether the execution permission has been outputted by the data managing section. A method of failure diagnosis is also disclosed.

Abstract: The electronic control apparatus includes a control section supplied with electric power through a power switch to operate, and a timer circuit always supplied with electric power to operate irrespective of an on/off state of the power switch. The control section is configured to perform a process in which the timer circuit is caused to make a reset-start after a frequency of a clock used in the timer circuit is changed from a first frequency for counting operation to a second frequency higher than the first frequency, and a process in which it is determined whether or not a count value of the timer circuit has reached its upper limit value when it is detected that a predetermined time has elapsed after the reset-start of the timer circuit on the basis of a count value of an internal timer of the timer circuit.

Abstract: A failure diagnosis apparatus for a vehicle is disclosed. The apparatus includes a diagnosis processing section for executing failure diagnosis processing on a device of the vehicle to generate a diagnosis result. The apparatus also includes a data managing section for managing data of the diagnosis result. After an execution condition is met for failure diagnosis, the diagnosis processing section outputs an execution demand to the data managing section for the failure diagnosis processing. In response to the execution demand, the data managing section outputs an execution permission to the diagnosis processing section for the failure diagnosis processing. Also, after the execution condition is met for the failure diagnosis, the diagnosis processing section starts executing the failure diagnosis processing regardless of whether the execution permission has been outputted by the data managing section. A method of failure diagnosis is also disclosed.

Abstract: A secondary air supply abnormality detection system determines that an abnormality is generated in a system including a secondary air supply system if a true secondary air flow rate is out of a predetermined range. The true secondary air flow rate is calculated by subtracting a secondary air flow rate average at the time when an air pump is not operating from another secondary air flow rate average at the time when the air pump is operating. Thus, variation in the secondary air flow rate due to change with time or production tolerance can be suitably corrected. Since calculation accuracy of the true secondary air flow rate is improved, determination accuracy of the abnormality in the system including the secondary air supply system can be improved.

Abstract: A secondary air supply abnormality detection system determines that an abnormality is generated in a system including a secondary air supply system if a true secondary air flow rate is out of a predetermined range. The true secondary air flow rate is calculated by subtracting a secondary air flow rate average at the time when an air pump is not operating from another secondary air flow rate average at the time when the air pump is operating. Thus, variation in the secondary air flow rate due to change with time or production tolerance can be suitably corrected. Since calculation accuracy of the true secondary air flow rate is improved, determination accuracy of the abnormality in the system including the secondary air supply system can be improved.

Abstract: In an engine exhaust catalyst warm-up control, ignition timing is delayed from normal first to raise the catalyst temperature, and then a fuel injection amount is dithered to increase and decrease alternately from a normal amount until the catalyst temperature reaches the catalyst activation completion temperature. In place of the ignition delay control, afterburning control may be employed in which fuel cut for a cylinder and fuel increase for the other cylinders are executed. Further, the catalyst warm-up control may be performed by controlling a supercharging operation and an exhaust gas recirculation operation cooperatively.