Micsig ATO1000 Series, Руководство пользователя

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Figure 3-14 Camshaft position sensor (Hall type)
3.2.5 Coolant Temperature
The coolant temperature sensor is usually called a water temperature sensor. Generally, it contains a thermistor. As
the temperature increases, the resistance becomes smaller, which causes the output voltage to change, and the water
temperature changes slowly, so the voltage also changes slowly. Different models have different performances, and
the output voltage can increase with the water temperature, it can also decrease with the water temperature.
However, there is a special sensor called the Vauxhaus sensor. The output voltage of this sensor is 3-4V when the
vehicle is cold. As the vehicle starts, the temperature rises and the voltage gradually decreases. It is generally 1V
during normal operation, but with As the vehicle temperature rises, when the vehicle temperature reaches 40-50
degrees, the ECM will switch the voltage to make the sensor voltage rise rapidly to 3-4V, so as to achieve more
accurate voltage output at high temperatures.
Use a BNC to banana cable, one end is connected to channel 1 of the oscilloscope, the other end is grounded with
the black plug, and the red connector is connected to the signal wire of the coolant sensor (the ground wire of the
coolant) with a needle probe.
Use ATO oscilloscope to test the coolant temperature sensor, the specific operation is shown in Figure 3-15: