Geely EC715 2009, Workshop Manual

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Knock sensor is a frequency response sensor, installed in the
engine block the most sensitive to knocking part, the lower
intake manifold. ECM uses knock sensor to detect knock
intensity, and then to adjust the ignition advance angle, to
effectively control knocking and optimize the engine power, fuel
economy and emission levels. If the engine knocking occurs,
ECM will receive the signal, filter out the non-knock signals and
determine engine cycle calculated by camshaft and crankshaft
position sensor signals. ECM determines the cylinder in which
the knock occurs and will delay the ignition advance angle for
this cylinder until the knock disappears. Then ECM advances
the ignition advance angle until the ignition angle is best suited
for the operating conditions at that time. Sensor signals pass
through ECM harness connector EN01 terminal No.30,31 to
ECM. DTC code P0327, P0328 will be recorded by ECM where
there is a KS sensor malfunction.
5. Throttle Position Sensor (TPS)
FE02-5126b
Throttle position sensor is installed on the throttle body
connected with the throttle shaft. Within the sensor, it is actually
a sliding variable resistor, with a 5 V reference voltage and a
ground provided by ECM. Engine control module monitors the
signal voltage to calculate the throttle position. Because it is
connected with the throttle shaft, so the output signal changes
as the movement of the accelerator pedal. When the throttle is
closed, the sensor output voltage is low, about 0.3-0.9 V. With
the throttle opening the output voltage increases, when the
throttle is fully open, the output voltage is about 4.5 V. Sensor
signals passe through ECM harness connector EN01 terminal
No.26 to ECM, ECM adjusts fuel injection amount based on
this signal. DTC code P0122, P0123 will be recorded when
there is a sensor circuit malfunction.
6. Engine Coolant Temperature Sensor (ECT)
FE02-5127b
Engine coolant temperature (ECT) sensor is a thermistor and
its resistance changes as the temperature changes. It is
installed in the engine coolant flow. When the coolant
temperature is low, the resistance is high. At -30 °C (-22 °F)
the resistance is 26,000 Ω; at 130 °C (266 °F), the resistance
is 90 Ω. ECM provides a 5 V voltage to the sensor. When the
engine is cold, the voltage is high. When the engine is hot, the
voltage is low. The coolant temperature signal is important to
the ignition timing and fuel injection adjustment, while the signal
is also transmitted to the instrument panel (IP) through the CAN
network, used to display the current engine working
temperature. Sensor signals pass through ECM harness
connector EN01 terminal No.41 to ECM. DTC code P0117,
P0118 will be recorded when there is a sensor or circuit
malfunction.
7. Vehicle Speed Sensor (VSS)
FE02-5128b
2-16 Control System JL4G18-D Engine
EC718/EC718RV EC715/EC715RV 10/2009