| 摘要 |
PURPOSE:To stop fixed injection of fuel when a fixed ignition system has become inoperative, by employing such an arrangement that the timing at which a fixed injection control circuit of a backup circuit used when a micro computor has caused runaway produces output signals is synchronized with signals relating to ignition. CONSTITUTION:In normal operation of a micro computor 7, it carries out calculation by use of a reference signal, a rotation signal, a starting signal and an idle signal and gives an ignition signal and a fuel injection signal respectively to an ignitor 13 and an injector 17 via selector circuits 11, 12. Here, arrangement is such that, if runaway of the micro computor 7 is detected by a runaway supervising circuit 10, a fixed ignition control circuit 8 producing a fixed ignition signal in synchronism with the reference signal and the rotation signal and a fixed injection control signal 9 producing a fixed injection signal in synchronism with a high voltage produced at the secondary side of an ignition coil 14 are used selectively by the selector circuits 11, 12. Further, the fixed injection control circuit 9 is designed to determine the injection time from the conditions of the starting signal or the idling signal. |
