Patent ID: 8695411

Claim:
An oil-pressure determination apparatus of an engine, comprising: an oil pump driven by the engine; an oil supply passage supplying oil from the oil pump to engine components therethrough; a relief mechanism provided in the oil supply passage to relieve the oil so as to restrain an increase of an oil pressure of the oil; an oil pressure switch operative to switch an output-signal state thereof between a conductive state and a non-conductive state when the oil pressure exceeds a specified setting oil-pressure; a determination device determining a malfunction state of the oil pressure based on switching of the output-signal state of said oil pressure switch; a temperature sensor detecting temperature of engine cooling water or the oil; and an engine speed sensor detecting an engine speed, wherein said determination device is configured such that determination of the malfunction state of the oil pressure based on the output-signal state of the oil pressure switch is not executed until the engine speed detected by said engine speed sensor reaches a specified lower-limit engine speed, but starts after the engine speed reaches the specified lower-limit engine speed, and said specified lower-limit engine speed for determination start is set to be variable according to the temperature detected by said temperature sensor.