An electronic control apparatus comprises a nonvolatile memory, operating means, determining means and retrying means. The nonvolatile memory stores predetermined data and has a memory region which is divided into a plurality of sub-regions. The operating means executes a check operation for each of the sub-regions in order to check whether the data stored in the nonvolatile memory are normal or not. The determining means determines whether the check operation has detected any data errors. The retrying means allows the operating means to retry the check operation for a predetermined number of times for the sub-regions that have been determined to be in data error by the determining means.