| 摘要 |
PROBLEM TO BE SOLVED: To efficiently execute diagnostic communication and also to prevent the processing delay of engine control by judging the load of a software in engine control which changes in accordance with the traveling state, etc., of a vehicle, controlling the timing parameter of diagnostic communication within a standard and controlling the software load of diagnostic communication. SOLUTION: In an on-vehicle engine control system where engine control and diagnostic communication are executed in parallel, the diag 13 of an engine control computer (ECU) 1 diagnoses a fault based on data concerning a vehicle state such as an inputted traveling state, etc., and outputs fault diagnostic data by communication with an external tool 2 through a communication part 14. Here, the largeness of the load of the software in changing engine control is judged in accordance with the vehicle state, the timing parameter of diagnostic communication is controlled within the standard (ISO9141) in accordance with a judgement result and the software load for diagnostic communication is controlled so as to prevent the processing delay of engine control and also to efficiently execute diagnostic communication. |
