USB Autoscope

Analytics and diagnosctic equipment for automotive industry

Temperature sensor

Temperature sensor is temperature sensitive semiconductor resistor, which usually has negative temperature coefficient (NTC), meaning that the resistance goes down with increasing temperature. The opposite type – positive (PTC) is very rare.
Application:

  • engine coolant temperature sensor;
  • air temperature sensor;
  • oil temperature sensor;
  • fuel temperature sensor.

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Output voltage waveform from a properly functioning engine coolant temperature sensor.  Output voltage of an NTC‑sensor decreases with increasing temperature, due to the way the circuit is designed.

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Output voltage waveform from a malfunctioning engine coolant temperature sensor. The sensor circuit develops an intermittent connection as the sensor heats up.

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Output voltage waveform from a malfunctioning engine coolant temperature sensor.

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Output voltage waveform from a properly functioning intake air temperature sensor (Toyota Avensis 1.8i 2007).

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Output voltage waveform from a properly functioning intake air temperature sensor. (KIA Ceed 1.6 2013).

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Output voltage waveform from a properly functioning fuel temperature sensor of diesel engine.

The USB Oscilloscope program is required for waveform playback. Get the latest USB Oscilloscope program here.