| 摘要 |
PURPOSE:To facilitate checking operations of various detecting switches, by a construction wherein whether or not the operations of a plurality of detecting switches for detecting information on the condition of an engine are normal can be checked at a checking terminal. CONSTITUTION:After a key switch is turned ON, when an accelerator pedal is depressed and with the result that the opening of the throttle valve exceeds a predetermined value alpha and an idle switch 1 is turned ON, a transistor Tr1 is turned OFF, and the potential at a point (a) is raised to a high level. At this time, since a WOT switch 4 for detecting the full opening of the throttle valve remains OFF, an output from an AND circuit 6 is at a low level, a transistor Tr3 is turned ON through an inverter IN, and a voltage of 0V is measured at the checking terminal 7. When the switch 4 is subsequently turned ON, the output from the AND circuit 6 becomes high level, and a voltage VB is measured at the terminal 7. In this case, when the switch 1 and/or the switch 4 is in an abnormal condition, the transistors Tr1, Tr2 remain ON, and a voltage of 0V is measured at the terminal 7. |
