摘要 |
A control unit of a self-diagnosis apparatus for a vehicle includes a CPU and a non-volatile RAM, wherein the CPU has a function of detecting abnormalities occurring in vehicle-mounted devices and of inputting diagnostic data for the vehicle-mounted devices necessary for the analysis of detected abnormalities. In the case of an abnormality occurring in a particular vehicle-mounted device during two consecutive trips, the abnormality is judged to be a final abnormality, whereas an abnormality of the particular vehicle-mounted device detected during the first trip was judged to be only a temporary abnormality. Moreover, updating of the diagnostic data is inhibited for a second abnormality as is subsequent final storage of the diagnostic data for an abnormality occurring in the second vehicle-mounted devices. If a further abnormality of the first vehicle-mounted device is detected again during a second trip, it is judged to be a final abnormality and thus an abnormality code is set in RAM and the diagnostic data is frozen by inhibiting any update of the diagnostic data. If the abnormality of the first vehicle-mounted device is not detected during the second trip, the temporary abnormality is cancelled. Thereby, the present invention makes it possible to more accurate and pertinent store diagnostic data for the analysis of abnormalities in vehicle-mounted devices.
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