User's Manual

iSmartEV P03 User Manual
www.newsmartsafe.com
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(2) Inspection of knock sensor output signal
Unplug the connecting plug of the knock sensor and check the
voltage between the knock sensor connecting terminal and the
grounding with the "AC voltage" measuring gear when the engine
is idling. There should be pulse voltage output. If not, the knock
sensor must be replaced.
Detection of cooling water temperature sensor
(1) Resistance detection of cooling water temperature sensor
On-vehicle inspection: Turn the ignition switch to OFF position,
remove the cooling water temperature sensor wire connector, and
test the resistance value between the two terminals of the sensor
via resistance measurement. The resistance value is inversely
proportional to the temperature (negative temperature coefficient),
and shall be less than 1KΩ when the engine is hot.
Single piece inspection: Unplug the cooling water temperature
sensor wire connector, and then remove the sensor from the
engine. Place the sensor in the water in the beaker, heat the
water in the beaker, and measure the resistance value between
the two terminals of the water temperature sensor under
different water temperature conditions via resistance
measurement. Compare the measured value with the standard
value. If it does not meet the standard, the water temperature
sensor should be replaced.
(2) Output signal voltage detection of cooling water temperature
sensor
Install the cooling water temperature sensor and plug the wire
connector of the sensor. When the ignition switch is turned to
the ON position, test the sensor output voltage signal from the
two terminals of the water temperature sensor wire connector.
The measured voltage value shall change inversely with the