Abstract: A vehicle diagnosis system includes an electronic control unit, which executes a diagnosing process for determining whether any abnormality is present in a vehicle based on signals from vehicle devices. When any abnormality is detected, the electronic control unit stores in an EEPROM a diagnosis result indicative of the abnormality when a storage permission flag in the EEPROM is in the on-state. The storage permission flag is turned on from the off-state when receiving a storage permission command from an external unit. Thus, the storage of the diagnosis result into the EEPROM may be permitted at the time of transmitting the storage permission command externally to the ECU.

Abstract: An electronic control apparatus includes a control circuit and has a power supply holding function whereby when a power switch-off command is received by the apparatus, the supplying of power to the control circuit is continued until it has completed specific processing, during a power supply holding interval. The duration of each such interval is measured and stored in non-volatile memory, and subsequently used for detecting any power supply holding function abnormality, and for ensuring that the specific processing is actually performed, and distinguishing between an abnormality causing premature switch-off and an abnormality causing failure to terminate the supplying of power.

Abstract: An engine control unit has a data memory for storing freeze frame data that is data indicating the operating status of vehicle equipment at the time when an abnormality of the vehicle equipment is detected. The engine control unit saves the freeze frame data stored in the data memory in a storage unit of a management station outside the vehicle through radio communication. The engine control unit determines the properness of the communication and performs a memory operation for erasing the relevant freeze frame data from the data memory based on a determination that the communication has been properly performed.

Abstract: An electronic control apparatus includes a control circuit and has a power supply holding function whereby when a power switch-off command is received by the apparatus, the supplying of power to the control circuit is continued until it has completed specific processing, during a power supply holding interval. The duration of each such interval is measured and stored in non-volatile memory, and subsequently used for detecting any power supply holding function abnormality, and for ensuring that the specific processing is actually performed, and distinguishing between an abnormality causing premature switch-off and an abnormality causing failure to terminate the supplying of power.

Abstract: A vehicle controller self-diagnosis apparatus having areas such as memory information, tables, and the like relating to abnormality-detection processing that can be easily modified when abnormal-detection targets are increased or decreased, thereby reducing the amount of time required to implement such changes. An abnormality-diagnosis program of the present invention includes an abnormality-detection object, an abnormality-verification object, and an abnormality-processing object. The abnormality-detection object is provided with a program of object-oriented design to determine normality or abnormality based on information from several sensors. The abnormality-verification object is provided with a program of object-oriented design to process a flag set by the abnormality-detection object.