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Coolant Temperature Sensor Waveform Notes
The Coolant Temperature Sensor (CTS) will invariably be a two wire device with a voltage supply at approximately 5 volts. The sensor itself has the ability to alter its resistance with engine temperature change. The majority of sensors have a Negative Temperature Coefficient (NTC) which results in the resistance of the component decreasing as the temperature increases. The resistance change will therefore alter the voltage seen at the sensor and can be monitored for any discrepancies across its operational range.
By selecting a time scale of 500 seconds, connect the oscilloscope to the sensor and observe the output voltage. Start the engine and in the majority of cases the voltage will start in the region of 3 to 4 volts however this voltage will depend on the temperature of the engine, as the temperature increases the resistance decreases and the voltage will also be seen to drop. The rate of voltage change is usually linear with no sudden changes to the voltage, if the CTS displays a fault a certain temperature, this is the only true way of detecting it.
The Vauxhall Simtec system has a point at which the voltage alters dramatically during the warm up period, this is described in the notes section of the Coolant Temperature Sensor (Vauxhall) waveform page.
汽車診斷 | 汽車診斷儀 | 汽車故障診斷儀 | 汽車測(cè)試儀 | 汽車分析儀 | 汽車診斷示波器 | 汽車電路測(cè)試儀 | 汽車電路分析儀 | 發(fā)動(dòng)機(jī)分析儀 | 發(fā)動(dòng)機(jī)綜合分析儀 | 發(fā)動(dòng)機(jī)檢測(cè)中心 | 點(diǎn)火分析儀 | 點(diǎn)火測(cè)試儀 | 汽車傳感器測(cè)試儀 | CAN總線示波器 | LIN總線示波器 | 汽車故障記錄儀 | 汽車傳感器分析儀 | 汽車檢測(cè)儀 | 噴油嘴測(cè)試儀 | 點(diǎn)火線圈測(cè)試儀 | 蓄電池測(cè)試儀 | 發(fā)電機(jī)測(cè)試儀 | 起動(dòng)機(jī)測(cè)試儀 | ABS傳感器測(cè)試儀 | ECU測(cè)試儀 | ECM測(cè)試儀 | 進(jìn)氣真空/壓力測(cè)試儀 | 排氣壓力測(cè)試儀 | 汽車技術(shù)培訓(xùn) | 爆震傳感器測(cè)試儀 | 缺火測(cè)試儀 | 缺缸測(cè)試儀 | 線路測(cè)試儀 | 引出線 | 汽車數(shù)字示波器 | 真空傳感器 | 高壓感應(yīng)測(cè)試頭 | 無分電器點(diǎn)火測(cè)試頭 | 獨(dú)立點(diǎn)火（COP）感應(yīng)測(cè)試頭 | 漏電測(cè)試儀 | 氣缸相對(duì)壓縮測(cè)試 | 電腦測(cè)試儀 | 發(fā)動(dòng)機(jī)控制器測(cè)試儀 | 泄漏測(cè)試儀 | 熒光檢漏 | 超聲波檢漏 | 汽車數(shù)字萬用表 | 電流鉗表 | 電流勾表 | 點(diǎn)火正時(shí)燈 |
