Waveforms

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.
Output voltage waveform from a properly functioning engine coolant temperature sensor
Output voltage waveform from a properly functioning engine coolant temperature sensor

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.

Output voltage waveform from a malfunctioning engine coolant temperature sensor

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

Output voltage waveform from a malfunctioning engine coolant temperature sensor.

Output voltage waveform from a malfunctioning engine coolant temperature sensor.

Output voltage waveform from a properly functioning intake air temperature sensor

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

Output voltage waveform from a properly functioning intake air temperature sensor

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

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

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