| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and device for failure diagnosis of a MAP (Manifold Air Pressure) sensor to show the internal air pressure of an intake manifold, capable of easily judging any failure in the output of the MAP sensor such as a distortion even if the output voltage value lies between the upper and lower limit values. SOLUTION: Judgement is made whether the output signal of the MAP sensor is within the set range, and the air pressure is calculated on the basis of the engine operating condition(s), and if the judgement passed shows that the output signal is within the set range, a judgement is made whether the difference between the air pressure indicated by the output signal of the MAP sensor and the air pressure according to the calculation is smaller than the set value, and in case the output signal of the MAP sensor does not lie within the set range at the stage of judging the output signal or in case the difference between the air pressure indicated by the output signal of the MAP sensor and the air pressure according to the calculation is not smaller than the set value at the stage of comparison, the calculated pressure is set as the air pressure. COPYRIGHT: (C)2004,JPO
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