4. Camshaft Position Sensor (CMP)
FE02-5362b
Camshaft position sensor is a Hall-effect sensor, which is
installed in the vicinity of the intake camshaft, and works
together with camshaft signal wheel. The signal wheel is
corresponding to the specific engine location. ECM measures
digital voltage signal through the sensor, therefore determining
the working cylinder and to implement one to one control.
Engine control module then calculates the actual sequence of
fuel injection. If the engine is running when the camshaft
position sensor signal is lost, the fuel injection system will be
converted to fuel injection order based on the final fuel injection
pulse, while the engine continues to run. If the engine starts
after being shut down, the fuel injection will be converted from
sequential injection to group injection. Even if the fault exists,
the engine can be restarted.
5. Engine Coolant Temperature Sensor (ECT)
FE02-5127b
Engine coolant temperature (ECT) sensor is used to detect the
engine operating temperature. ECM provides the best control
scheme depending on the temperature. The sensor uses a
negative temperature coefficient thermistor as the sensing
element, when the coolant temperature rises, the resistance
decreases. At -30 ° C (-22 ° F) the resistance is 26000 Ω; at
130 ° C (266 ° F), the resistance is 90 Ω. The sensors is
installed in the main coolant path. 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.
6. Knock Sensor (KS)
FE02-5125b
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.
Due to weak sensor signals, the sensor wire has a shielded
cable. Its resistance is 1M Ω, in any case the output signal is
greater than 17mV / g
Engine
Control System JL4G15-D
2-589
EC718/EC718RV EC715/EC715RV 10/2009
Summary of Contents for EC715 2009
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