| 摘要 |
PURPOSE:To make it diagnosable with either way of voltage and current driving systems, by comparing an injector driving signal with first and higher second reference values, while taking up a logical operator of these output values, in case of an electronically controlled fuel injection device. CONSTITUTION:An injector driving signal 10 is compared with forst reference voltage out of a partial pressure part 14 at a first comparator 1, and also compared with higher second reference voltage out of a partial pressure part 15 at a second comparator 2, generating flyback voltage, and this voltage and the output via a one-shot circuit 3 are compounded with a logical circuit 4. When an output pulse of this logical circuit 4 fails to generate for the specified period of time, a reference clock 5 is counted with a counter 6 and, after the elapse of the specified time, time width to be outputted from a flip-flop 7 is processed with a microcomputer 8 whereby injector driving pulse width is securable. With this constitution, no matter what a driving system for an injector is of voltage or current method in type, a diagnosis for the injector is performable with the same measuring device. |
