Abstract: The electronic control apparatus includes a rewritable nonvolatile memory, a first function of performing a monitoring operation to detect abnormalities in each of a first to N-th (N being an integer larger than 2) items, and a second function of, when the first function detects an abnormality in an M-th (M being an integer larger than 1 and not larger than the N), storing an abnormality code indicative of the detected abnormality in the rewritable nonvolatile memory. The second function is configured to store an identification information associated with the M-th item so that the M-th item can be identified from the first to N-th items in the rewritable nonvolatile memory.