| 摘要 |
PROBLEM TO BE SOLVED: To provide an engine control unit capable of generating a normal crank angle signal synchronized with a crank angle of an engine even if a latch circuit fails and eventually continuing engine operation.SOLUTION: An engine control unit generates a crank angle signal by a latch circuit 31a on the basis of a detection signal of an electromagnetic pickup 32 fluctuating synchronously with a reluctor protrusion 7a during actuation of an engine 1, and executes an ignition timing control. The engine control unit measures real reluctor time Treal corresponding to an ON-period of the crank angle signal and calculates estimated reluctor time Test from an engine revolving speed Ne (S2, S6). The engine control unit calculates a reluctor ratio r as a comparison of the real reactor time Treal with the estimated reluctor time Test (S8). If the reluctor ratio r is lower than a determination value r0, the engine control unit assumes that the latch circuit 31a fails and determines fail (S10, S14), and executes the ignition timing control on the basis of the estimated reluctor time Test in place of the real reluctor time Treal (S16). |
