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Chery A15. Manual - part 32

Troubleshooting: The common malfunctions of the
fuel pump are representation of insufficient fuel
pressure, not pumping fuel and so on. It shall be
verified firstly in troubleshooting that the fuel pressure
is within rated range and the pipeline is leaked. In
addition both the positive and negative pressure of the
fuel tank will have impacts on the fuel system.

※Solenoid fuel injector

Function: The fuel injector supplies atomized fuel to
the engine through injecting the fuel within the required
time according to the demand from the ECU.

Structure and working principle: The ECU sends the
electrical pulse to the fuel injector coil for generate a
magnetic force. If the magnetic force is increased
enough to overcome the composite force of the release
spring pressure force, the gravity force of needle valve,
and the friction force, the needle valve will begin to
rise and the fuel injection will start. The maximum lift
range of the needle valve is no more than 0.1mm.
When the fuel injection pulse ends, the pressure force
of the release spring will make the needle valve close
again.

Notes on installation: Only the specific connector can
be used in the fixed fuel injector and shall not be
mixed.
For the convenience of installation it is recommended
that the upper O ring connected to the fuel distributor
pipe shall be coated with silica-free clean oil. Pay
attention not to make oil contaminate the inside of the
fuel injector and the injection hole.
Place the fuel injector in the fuel injector base in
vertical direction and fasten the injector on the base by
the clasp.

Note: As for the car not being used for a long time, it is
possible that such car can not start properly because the
coagulation of fuel in the fuel injector. Under such
circumstance verify carefully that the fuel injector is
coagulated.

Fault diagnosis: The electrical injection system of A15
RHD car can conduct fault diagnosis on the driving
stage of the fuel injector in stead of conducting fault
diagnosis on its self. If the driving stage of the fuel
injector is short or overloaded to the battery power
supply short to ground or open the malfunction flag

G-16

supply, short to ground or open, the malfunction flag
bit is set. The closed loop control of the oxygen sensor
and its memory precontrol are disabled, but the last
data stored in its memory is valid. After the
malfunction is fixed, the malfunction flag bit will be
reset.

Working pressure: 350 kPa

Resistance of the fuel injector: 11-16

Ω

Pins： Each fuel injector has two pins. Of which the
one marked by “+” is connected to the 87# pin of
output terminal of the fuel pump relay; the other is
connected to the 27#, 6#, 7#, or 47# pin of the ECU
respectively.

Troubleshooting: The common malfunctions of the
fuel injector such as unsmooth fuel injection and
defective atomization are normally resulted due to long
term use of the engine. So the fuel injector shall be
cleaned periodically. The circuit short or open in the
internal coil of the fuel injector also will result
malfunction of the fuel injection system. Verify that the
system circuits are short or open.

※ Idle actuator with step motor DLA

Function: The idle actuator with step motor is also
equipped with a bypass air intake duct. If the throttle is
closed air can enter the engine through such bypass
duct. The ECU can adjust the sectional area of the
bypass duct through this step motor, control the air
intake flow and in turn control the quantity of fuel
injection based on the air flow. The increase or
decrease of the engine rotary speed can be achieved
through increasing or decreasing the sectional area of
the bypass duct under idle speed, through which the
closed loop control of engine rotary speed under idle
speed is achieved eventually.

Connected to the
87# pin of the
main relay

Circuit diagram of the solenoid fuel injector

Idle actuator with step motor

G-17

Structure and working principle: The step motor is a
micro-motor, which is comprised of steel stators
installed in a circle and a rotor. Each steel stator has a
coil. The rotor is permanent magnet and the center of
the magnet is a nut. All the coils of stators are always
on. If the current direction of any coil is changed, the
rotor will turn by an angle. If all coils of stators change
their currents directions in a proper order, a rotating
magnetic field will be generated and result in the
permanent magnet rotor rotating in designed direction.

Fault diagnosis: The ECU can detect the circuit short
and circuit open in the two coils of the idle step motor.
Upon the occurrence of such malfunction the engine
malfunction alarm light will be lit and the engine will
enter the malfunction operation mode.

Pins:

Pin A is connected to the 29# pin of ECU;
Pin B is connected to the 4# pin of ECU;
Pin C is connected to the 26# pin of ECU;
Pin D is connected to the 21# pin of ECU.

Troubleshooting: Verify that the four circuits between
the step motor and the ECU are short or open. Verify
that the step motor is jammed. Verify that there is
circuit short or circuit open inside the step motor.

※ Ignition coil ZSK-ROV

Function: The ignition coil transforms the low voltage
of the primary winding into the high voltage of the
secondary winding. The spark plug generates the spark
through discharging and ignites the combustion gas
mixed with air and fuel.

Structure and working principle: The ignition coil is
comprised of the primary winding, the secondary
winding, the iron core, the shell and so on. If the
battery voltage applies on the primary winding, the
primary winding is charged. After the ECU cut off the
circuit of the primary winding the charging will be
stopped and the high voltage will be inducted in the
secondary winding.

Fault diagnosis: Because the ECU is not able to
conduct diagnosing for the ignition coil, there is no
diagnostic trouble code for the malfunction of the
ignition coil. Whether the ignition coil functions
properly can be judged only by inspecting the ignition

i t

Th i iti

l t

Circuit of the stepper of the idle

The step motor
of the idle actuator

External appearance of

G-18

coil resistance. The ignition coil produces quite a lot
heat under normal operation and the over temperature
of ignition coil will result in such malfunctions as
increase of the ignition coil’s resistance, unstable
operation of the engine and engine stall.

Primary winding: 0.47 ohms

Secondary winding: 8 ohms

Pins:

1# pin of the primary winding is connected to the 5#
pin of ECU;
2# pin of the primary winding is connected to the 2#
pin of ECU;
3# and 4# pins are jointly connected to the positive grid
of power supply.

High voltage side: 1#, 2#, 3# and 4# pins are
connected respectively to the spark plug of the cylinder
with the same number through the distributor circuit.

Troubleshooting: Verify that there is circuit short or
circuit open in the coils.
Verify that there is electrical leakage and crack on the
shell.
Verify that the electricity for ignition is not sufficient
due to coil ageing.

※Carbon canister control valve

Function: It is used to control the purge airflow of the
carbon canister. The carbon canister control valve is
controlled by the ECU through the pulse length and
frequency (i.e. duty ratio) based on the engine load.
The excessive accumulation of fuel vapor in the carbon
canister will result in fuel spill and environment
pollution, so the function of the solenoid valve of the
carbon canister is to open the valve at an appropriate
time so that the excessive fuel vapor can enter the air
intake pipe and participate in the combustion.

Structure and working principle: The carbon canister
is comprised of magnetic coil, armature, valve and
other elements. There is a filter screen at its inlet. The
airflow passing the carbon canister control valve is not
only relative to the duty ratio of the pulse which is sent
by the ECU to the carbon canister control valve, but
also relative to the pressure difference between the exit
and inlet of the carbon canister control valve. If there is
no pulse, the carbon canister control valve is closed.

Ignition coil with double spark

87# main relay

Circuit diagram of the ignition coil

G-19

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