| 摘要 |
PROBLEM TO BE SOLVED: To prevent wrong decision in a vehicle in which a theft is prevented by making it possible for the vehicle to start up by recognizing a specified voltage difference by a normal key switch. SOLUTION: A power terminal B and a decision terminal S are provided at a control unit 2 for controlling the ignition of an engine, and a constant- voltage diode ZD1 for inputting a lower decision-voltage than power-supply voltage to the decision terminal S is provided at an engine starting key switch 1. Further, a constant-voltage diode ZD2 having the same characteristic as that of the constant-voltage diode ZD1, is provided at a control unit 2 with a CDI circuit 3 for controlling the ignition, and a circuit for outputting signals permitting the CDI circuit 3 to control the ignition through a CPU 6 for decision when the voltage difference across both terminals B.S is about the same, is formed of transistors Q1 and Q2. Thus, the width of decision can be narrowed, and even when the environmental condition is different, the same characteristic can be displayed. As a result, the decision to use a normal key switch can be always made with high accuracy. |
