Geely EC718, EC718RV, EC715, EC715RV. Manual part — 25

2. Camshaft Position Sensor (CMP)

FE02-5122b

Engine control module receives this signal as a sync pulse,
according to an appropriate sequence to trigger the fuel
injectors. Engine control module uses the camshaft position
sensor signals to instruct cylinder No.1 piston position during
power stroke. Engine control module then calculates the actual
fuel injection sequence. If when the engine is running, the
camshaft position sensor signal is lost, the fuel injection system
will be converted to a fuel injection pulse based on the previous
calculation of the fuel injection model, while the engine will
continue to run. Even if the fault exists, the engine can be
restarted. Sensor signals pass through ECM harness
connector EN01 terminal No.42 to ECM. When the engine is
running if the control module detects an incorrect camshaft
position sensor signal, it will record DTC code P0340, P0341,
P0342, P0343. DTC code P0016 will be recorded when the
crankshaft relative position is incorrect.

3. Intake Air Pressure and Temperature Sensor

FE02-5123b

Intake air pressure and temperature sensor has an intake
pressure sensing element and a thermistor. When the engine
is working, the engine intake pressure sensing element
produces the intake air pressure signal, negative temperature
coefficient thermistor produces intake air temperature signal.
This sensor detects intake manifold pressure change caused
by engine load and speed changes. These changes will be
converted to the voltage output. When the engine decelerates,
the throttle body closes resulting in a relatively low intake
manifold absolute pressure output. Intake manifold absolute
pressure and vacuum degree is opposite. When the manifold
pressure is high, the vacuum is low. MAP sensor is also used
to measure atmospheric pressure. This measurement is
calculated as part of the MAP calculation. When the ignition
switch is turned on and the engine is not running, the engine
control module reads atmospheric pressure as the intake
manifold pressure, and adjusts the Air-Fuel ratio accordingly.
With this kind of altitude compensation, the system can
maintain a low emissions while maintaining maneuverability.
Sensor signal passes through ECM harness connector EN01
terminal No.19 to ECM. When MAP sensor and its circuit
malfunction occurs, DTC P0105, P0106, P0107, P0108 will be
recorded. DTC code P0105, P0106, P0107, P0108 will be
recorded when MAP sensor and its circuit have malfunctions.
Engine control module provides 5V voltage to the thermistor
and measure the voltages change to determine the intake air
temperature. The engine control module obtains the intake air
temperature by measuring the voltage. ECM uses this signal
to adjust the injector pulse width and ignition timing. Sensor
signals pass through ECM harness connector EN01 terminal
No.25 to ECM. DTC code P0112, P0113 will be recorded when
there is a circuit malfunction.

4. Knock Sensor (KS)

FE02-5125b

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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

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The vehicle speed sensor is installed in the front transmission
case, connected with differential speed sensor drive gear.
Speed sensor is a Hall-style. The main relay controlled by ECM
provides the sensor working power. When the vehicle is
driving, the sensor output is a rectangular pulse signal. Sensor
signals pass through ECM harness connector EN01 terminal
No.57 to ECM. DTC code P0501 will be recorded when there
is a sensor or wiring malfunction.

8. Pre-Catalytic Heated Oxygen Sensor (HO

2

S)

FE02-5129b

Pre-Catalytic oxygen sensor is installed in the exhaust
manifold, the three-way catalytic converter front-end, detecting
the oxygen content of exhaust gas and sending ECM the
indirect mixture concentration. ECM adjusts fuel injection pulse
width, to make sure that the mixture ratio is close to the
theoretical value of about 14.7. Oxygen sensor has a sensing
element, which is a porous ceramic tube, the outer wall
surrounded by the engine exhaust and inside connecting to the
atmosphere. Sensing ceramic wall is a solid electrolyte
containing an electric heating tube. When the sensor ceramic
tube temperature reaches 350°C (662 ºF), it has a solid
electrolyte properties. Oxygen sensors work by converting
ceramic oxygen ion concentration difference between inside
and outside into a voltage signal output. The output voltage
level is due to movement caused internal electronic ceramic
tubes. If the mixture is rich, then the ceramic oxygen ion
concentration difference between inside and outside is high,
electrical potential difference is high, a large number of oxygen
ions move from the inside to the outside, the output voltage is
high (close to 800mV). If the mixture is lean, then the ceramic
oxygen ion concentration difference between inside and
outside is low, electrical potential difference is low, only a small
amount of oxygen ions move from inside to outside, the output
voltage is low (close to 200mV). Signal voltage suddenly

changes near the theoretical Air-Fuel ratio (λ=1). Sensor
signals pass through ECM harness connector EN01 terminal
No.45 to ECM. DTC code P0030, P0031, P0032, P0053,
P0130, P0131, P0132, P0133, P0134, P2195 , P2196 will be
recorded when there is a sensor, wire or circuit malfunction.

9. Post-Catalytic Heated Oxygen Sensor (HO

2

S)

Post-Catalytic oxygen sensor is installed on the three-way
catalytic converter rear end. Its working principle is the same
as the Pre-Catalytic oxygen sensor. If the three-way catalytic
converter is working properly, fuel control system is in close-
loop control, the sensor output voltage is stable at 0.45V.
Sensor signals pass through ECM harness connector EN01
terminal No.29 to ECM. DTC code P0036, P0037, P0038,
P0054, P0136, P0137, P0138, P0140, P2270, P2271 will be
recorded if there is a sensor, signal or circuit malfunction. DTC
code P0420 will be recorded if the Post-Catalytic oxygen
sensor detects that three-way catalytic converter is not working
properly.

10. Air-Conditioning Pressure Switch

Air-Conditioning pressure switch is installed in the Air-
Conditioning high pressure side pipeline, mainly for Air-
Conditioning system control. ECM command the compressor
control relay only when correct signal is received, so that the
electromagnetic compressor clutch pull-in. Switching signals
pass through ECM harness connector EN01 terminal No.10,
44 to ECM. DTC code will not be recorded when there is a
switch or circuit malfunction.

11. Power Steering Switch

Power steering switch is installed on the power steering pump.
When the steering wheel is operated, power steering pump oil
pressure changes due to increased power steering pump load.
If at this point, the engine is in idle state, it will cause the engine
idle fluctuate. In order to make the engine run smooth, after
ECM receives the signal, it will increase the engine's torque. A
typical way is to increase the fuel injection amount. Switching
signals pass through ECM harness connector EN01 terminal
No.12 to ECM. DTC code will not be recorded when there is a
switch or circuit malfunction.

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12. Defrost Heating Enable Input

The signal is provided by the BCM through a dedicated circuit
and is a voltage signal. The rear defrosting heating block is
essentially a resistance wire with fairly high heating power. The
power consumption is relatively high. When the rear defrost
heating starts, the generator load increases, causing the
engine speed fluctuate. In order to make the engine run
smoother, after ECM receives the signal, it increase the
engine's torque output. Switching signals pass through ECM
harness connector EN01 terminal No.24 to ECM. when the
signal fails, ECM does not record the relevant DTC code.

13. CAN Information Input

ECM downloads signals via CAN from the network for its own
needs. The most typical signals are: brake switch signal, ABS's
work status. CAN_HI signal circuit connects to other CAN
network modules through ECM harness connector EN01
terminal No.33. CAN_LO signal circuit connects to other CAN
network modules through ECM harness connector EN01
terminal No.34. If ECM fails to communicate with other
modules, it will record DTC code U0001, U0121, U0140,
U0151, P1523.

14. Serial Data Bus Input

When the ignition switch is turned on, the Anti-theft ignition coil
identifies whether the inserted key is an illegal key. The signal
is transmitted by the security module to ECM. ECM determines
whether to activate the engine Anti-theft locking system based
on this signal, such as cutting off the ignition, fuel injection, start
the circuit. ECM harness connector EN01 terminals No.15,23
are for serial data communication. The immobilizer system-
related failures DTC codes are P1610, P1611, P1612, P1613,
P1614.

2.2.2.3 Output Components

1. Idle Speed Control Valve (IAC)

FE02-5130b

Note

A. Do not to push and pull IAC valve core shaft, otherwise
it will damage the internal valve components.
B. When washing the IAC valve carbon residue, do not
let any cleaning agent enter the IAC valve inside,
otherwise it will damage IAC valve.

IAC valve is installed on the throttle body. ECM controls the
spool extended the amount to control the idle speed. Engine
sends the control module voltage pulses to the IAC valve motor
windings, so that IAC valve core shaft moves to the inside or
outside a certain distance (step or a count) with each pulse.
Shaft movement controls the air flow amount bypass the
throttle, and then controls the engine idle speed. The expected
idle speeds of all engine running conditions are programmed
and set in the ECM calibration program. These settings
includes engine speed based on engine coolant temperature,
speed, battery voltage, and Air-Conditioning system pressure.
Engine control module reads the correct IAC valve position to
meet the expectations of stable, warm-up idle speed under
different conditions. This information is stored in the engine
read-only memory, even after the ignition switch is switched off,
the information will not be cleared. If the engine control module
power supply is disconnect, it will lead to an incorrect idle speed
control. When starting, press the accelerator pedal half way
until the engine control module learns idle speed control. ECM
controls IAC valve through ECM harness connector EN01
terminals No.21,22,35,36. If the idle speed control valve
position does not match the actual ECM required location, DTC
code P0506, P0507 will be recorded. If idle speed control valve
circuit has a malfunction, DTC code P0508, P0509, P0511 will
be recorded.

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