发明名称 |
O2-sensor fault diagnosis apparatus and method therefor |
摘要 |
An O2-sensor fault diagnosis apparatus and method therefor, which are capable of detecting wire breaking of an O2-sensor with reliability and successively performing fault diagnosis with minimal effect on an exhaust gas. An O2-sensor 19 detects concentration of oxygen contained in an exhaust gas of an engine 1. An ECU 20 controls a quantity of fuel supplied to the engine 1 through feedback control according to an output signal of the O2-sensor. A fault diagnosis portion changes an input resistance value of an input circuit that is connected to the O2-sensor 19 and constitutes the ECU 20 each time a control condition for determining that the O2-sensor 19 is in an inactive state is satisfied, determines that wire breaking occurs in the O2-sensor 19 only if the output voltage of the O2-sensor 19 exceeds a predetermined voltage, and activates an informing portion to send a notice showing that there is a fault in the O2-sensor 19.
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申请公布号 |
US6818120(B2) |
申请公布日期 |
2004.11.16 |
申请号 |
US20010995677 |
申请日期 |
2001.11.29 |
申请人 |
MITSUBISHI DENKI KABUSHIKI KAISHA |
发明人 |
NAKAMICHI MASAKI;HANAZAKI RYOICHI |
分类号 |
G01D18/00;F02D41/14;F02D41/22;F02D45/00;G01N27/409;G01N27/417;G01N33/00;(IPC1-7):G01N27/407 |
主分类号 |
G01D18/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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