| 摘要 |
PROBLEM TO BE SOLVED: To enable the accuracy of diagnosing the abnormality of an air conditioner ECU to be improved in a system in which the abnormality of the air conditioner ECU is diagnosed by an engine ECU.SOLUTION: An abnormality diagnosis unit 34 for diagnosing the abnormality of an air conditioner ECU 33 and a monitor IC 35 for monitoring this abnormality diagnosis unit 34 are provided in an engine ECU 30. The abnormality diagnosis unit 34 determines whether the output signal of the air conditioner ECU 33 is normal or not using a prescribed criterion value, and thereby diagnosing the abnormality of the air conditioner ECU 33. At this time, the monitor IC 35 determines whether a criterion value used in diagnosing the abnormality of the air conditioner ECU 33 is normal or not, and the abnormality diagnosis unit 34 determines whether the monitor IC 35 is normal or not. When it is determined by the monitor IC 35 that the criterion value is abnormal, or when it is determined by the abnormality diagnosis unit 34 that the monitor IC 35 is abnormal, the abnormality diagnosis of the air conditioner ECU 33 is disabled, and a prescribed abnormality corrective action is executed.SELECTED DRAWING: Figure 2 |
