Patent ID: 8612089
Filing Date: 2013-12-17
Classification: G01M,G06F

Abstract:
1. An on-vehicle fault detecting device for detecting whether or not there has occurred a fault in the device itself or in its hardware component, the device comprising: data writing means for writing data in a memory; data reading means for reading data written in the memory: coincidence-of-data determining means for determining whether or not the data read by the data reading means from the memory is coincident with data intended to be written by the data writing means in the memory, wherein the device is operative to determine that there has occurred a hardware fault only in cases where the coincidence-of-data determining means determines that the read data is not coincident with the intended data to be written; usage-environment-information acquiring means for acquiring information about a usage environment around a vehicle equipped with the device; usage-environment-change determining means for determining whether or not the usage environment around the vehicle has changed on the basis of the usage environment information acquired by the usage-environment-information acquiring means, while it is continuously determined by the coincidence-of-data determining means that the read data is not coincident with the intended data to be written; and continuous-non-coincidence counting means for counting a number of times that the coincidence-of-data determining means continuously determines that the read data is not coincident with the intended data (hereinafter, also referred to as a number of times of continuous non-coincidence), wherein even in cases where the coincidence-of-data determining means has determined that the read data is not coincident with the intended data to be written, the device is operative not to determine that there has occurred a hardware fault unless the usage-environment-change determining means determines that the usage environment has changed; the data writing means is operative to again write the data in the memory, unless the number of times of continuous non-coincidence has reached a predetermined determination number of times of continuous non-coincidence, and the usage-environment-change determining means is operative to determine whether or not the usage environment around the vehicle has changed during a time period from the time of the first determination of continuous non-coincidence to the time when the number of times of continuous non-coincidence reaches the determination number of times of continuous non-coincidence, on the basis of the usage environment information acquired by the usage-environment-information acquiring means.