In-vehicle electronic control unit and method for abnormality response processing thereof

1. An in-vehicle electronic control unit comprising:

a control circuit configured to control an actuator mounted in a vehicle and to perform a self-diagnostic procedure;

a monitoring circuit operably connected to the control circuit and configured to monitor an operating state of the control circuit based on diagnostic information resulting from the self-diagnostic procedure; and

a relay controlled by, the monitoring circuit and configured to either allow or block a control signal output from the control circuit to the actuator;

a first memory operably connected to the control circuit and the monitoring circuit and configured to store and maintain the diagnostic information when the monitoring circuit makes an abnormality determination that the control circuit operates abnormally; and

a second memory operably connected to the control circuit and the monitoring circuit and configured to store and maintain the diagnostic information when the monitoring circuit makes a normality determination that the control circuit operates normally;

wherein the monitoring circuit is configured to make the abnormality determination when the diagnostic information satisfies a predetermined condition and to make the normality determination when the diagnostic information does not satisfy the predetermined condition,

wherein following the abnormality determination, the monitoring circuit is further configured to block the control signal, restart the control circuit, and communicate with an external entity, and

wherein the first memory is volatile memory and the second memory is a first non-volatile memory, and

wherein the monitoring circuit is further configured so that, when an ignition switch of the vehicle is turned off before the control circuit finishes storing the diagnostic information into the first non-volatile memory, the monitoring circuit performs self shut-off processing to transfer and store the diagnostic information from the volatile memory into a second non-volatile memory.

2. The in-vehicle electronic control unit according to claim 1 , wherein the predetermined condition is that the control circuit that operates abnormally still has an ability to perform the abnormality response processing.

3. The in-vehicle electronic control unit according to claim 2 , wherein when a portion of the control circuit other than any portion of an arithmetic unit has an abnormality, the control circuit still has the ability to perform the abnormality response processing.

4. The in-vehicle electronic control unit according to claim 1 , wherein the control circuit is configured to be enabled to perform normal-state processing when the diagnostic information stored in the first non-volatile memory is overwritten with diagnostic information indicating that the control circuit operates normally.

5. The in-vehicle electronic control unit according to claim 4 ,

wherein the control circuit is configured to be connectable to an external diagnostic device and replaceable with a new control circuit, and

wherein the control circuit is configured so that, when the control circuit is replaced with the new control circuit, and the external diagnostic device performs a diagnostic procedure on the new control circuit and determines that the new control circuit operates normally, the diagnostic information stored in the first non-volatile memory is overwritten with diagnostic information indicating that the new control circuit operates normally.

6. A method for abnormality response processing of an in-vehicle electronic control unit, the method comprising:

causing a control circuit configured to control an actuator mounted in a vehicle to perform a self-diagnostic procedure;

causing, when a monitoring circuit operably connected to the control circuit and configured to monitor an operating state of the control circuit based on diagnostic information resulting from the self-diagnostic procedure determines that the control circuit operates normally or abnormally,

the monitoring circuit either allows or blocks a control signal output from the control circuit to the actuator;

causing a first memory operably connected to the control circuit and the monitoring circuit and configured to store and maintain the diagnostic information when the monitoring circuit makes an abnormality determination that the control circuit operates a abnormally;

causing a second memory operably connected to the control circuit and the monitoring circuit and configured to store and maintain the diagnostic information when the monitoring circuit makes a normality determination that the control circuit operates normally;

wherein the monitoring circuit is configured to make the abnormality determination when the diagnostic information satisfies a predetermined condition and to make the normality determination when the diagnostic information does not satisfy the predetermined condition,

wherein following the abnormality determination, the monitoring circuit is further configured to block the control signal, restart the control circuit and communicate with an external entity, and

wherein the first memory is volatile memory and the second memory is a first non-volatile memory, and

configuring the monitoring circuit so that, when an ignition switch of the vehicle is turned off before the control circuit finishes storing the diagnostic information into the first non-volatile memory, the monitoring circuit performs self shut-off processing to transfer and store the diagnostic information from the volatile memory into a second non-volatile memory.