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X-431 Torque 5 User Manual
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knock sensor, “Resistance” can also be used to detect the coil resistance. The
resistance should be consistent with the specified value (Refer to the service
manual for the specific data). Otherwise, the knock sensor must be replaced.
(2) Check knock sensor output signal
Remove the knock sensor plug. Use
AC Voltage
to check the voltage between
the knock sensor wire terminal and ground when the engine is idling. There
should be a pulse voltage output. If there is no voltage output, replace the knock
sensor.
Cooling water temperature sensor test
(1) Detect coolant temperature sensor resistance
Check on the vehicle: Turn off the ignition switch, disconnect the coolant
temperature sensor wire connector, and use
Resistance
to test the resistance
between the two terminals of the sensor. Its resistance value is inversely
proportional to the temperature (negative temperature coefficient) and should be
less than 1kΩ during warm-up.
Single piece check: disconnect the coolant temperature sensor wire connector,
remove the sensor from the engine, place the sensor into the water in the beaker,
heat the water in the beaker, and use
Resistance
to test the resistance between
the two terminals of the sensor under different water temperature conditions.
Compare the measured value with the standard value. If the standard value is
not met, the coolant temperature sensor should be replaced.
(2) Detect coolant temperature sensor output signal voltage
Install the coolant temperature sensor, insert the sensor wire connector, turn on
the ignition switch, and test the sensor output voltage signal between the two
terminals of the coolant temperature sensor wire connector. The measured
voltage value should vary inversely with the coolant temperature. When the
coolant temperature sensor harness is disconnected and the ignition switch is
on, the voltage should be about 5V.
11.8.3 Attention
1. Before usage, please reset APP value on the multimeter to zero.
