Chery A11. Manual — part 153

Maintenance Manual for Chery·Windcloud

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Sunroof

5.2.5 Never fully shut sunshade with sunroof being open

during high-speed running.

5.2.6 In case electric control of sunroof dose not work, or

automatic shutting and sensoring failure, first

check sunroof fuse. If the fuse is normal, please

try reprogramming (refer to Maintenance Guide).

Page 37 of 37

Maintenance Manual for Chery·Windcloud

Marelli EFI System

Chapter One: Operating Principle for
Marelli EFI Control and Execute
Components

1. Intake Pressure and Intake Air
Temperature Sensor
Purpose: to detect absolute pressure of

intake manifold from 10-115KPa and intake

air temperature, to provide engine load

information, and to identify the height above

sea level and to conduct intake pressure

compensation according to the intake

pressure at certain engine speed and idle

speed.

Composition and principle: this sensor has

two functions (i.e. manifold absolute

pressure sensor and intake temperature

sensor integrated in one unit), and is

installed above pressure-stable cavity to

detect absolute pressure of intake manifold

(pressure-stable cavity), which is used to

control fuel injection and ignition.

Pressure-sensitive element inside intake
pressure sensor detects signal of intake

manifold pressure for injection pulse width

control of EFI system. This sensor also

serves as the substitute of a sensor of engine

load signal.
Intake air temperature sensing element is

an NTC (Negative Temperature Coefficient)

resistor, which is similar to that of water

temperature sensor. While the intake air

temperature increases, the resistance value

decreases. And engine ECU monitors the

variation of intake air temperature via a

comparison circuit inside.
Failure diagnosis: The monitor circuit

inside ECU detects sensor circuit troubles

such as open circuit, short circuit and sensor

damages, etc. In case ECU detects any

sensor output signal that goes beyond output

characteristic curve, the sensor is diagnosed

as failed by ECU.
For example: when intake pressure is

higher than upper limit or lower than lower

limit, ECU detects sensor failure (in case

that intake pressure is lower than lower limit

when starting, ECU is able to recognize the

starting condition), and the engine fault

indicating lamp goes on. Under this

condition the engine works in failure mode.

When intake temperature sensor signal

exceeds either upper or lower limit, engine

ECU will light fault indicating lamp to

remide driver that engine assumes failure

mode.

Installation: to be installed on pressurizer.
Troubleshooting: mainly check if there is

short circuit or open circuit on the

connection between 4 lines on senosr and

ECU.

If there is short circuit, open circuit or

grounding between sensor wire harnesses.

Check system for air leakage, and check if

all connections are in good condition.

Manifold absolute pressure /intake air temperature sensor

Intake temperature /
pressure sensor

Circuit diagram of manifold absolute pressure and intake

air temperature sensor

Pins: 1# is grounded (connecting ECU 54#);

2# outputs temperature signal

(connecting ECU 55#);

3# connects with standard 5V power

source (connecting ECU 68#);

4# outputs pressure signal (connecting

ECU 75#).

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Maintenance Manual for Chery·Windcloud

Marelli EFI System

2. Throttle Position Sensor

Purpose: this sensor is designed to provide
ECU with information of throttle angle. As
per such information, ECU obtains
information of engine load and operating
condition (for instance: start-up, idle speed,
reverse, partial load and full load) as well as
of acceleration and deceleration. This sensor
has three wires, and the throttle opening can
be detected by ECU via monitoring voltage
variation.
Composition and principle: Consisting of
two compass sliding contact resistors and
two sliding contact arms, throttle position
sensor is an angle sensor that outputs linear
signals. The axes of contact arms are on the
same axial line with throttle axis, with 5V
power supply voltage U

S

being applied to

both ends of each contact resistor. When
throttle turns, contact arms turn along with it
and move on sliding contact resisters,
educing potential of contacts U

P

as output

voltage. This sensor is actually an angle
potentiometer. ECU adopts Up/Us votage
ratio to avoid change in output signal due to
fluctuation in engine voltage.

Failure diagnosis: ECU monitors throttle
angle, and detects sensor failure when
output signal exceeds upper or lower limit.
In addition, ECU detects sensor circuit
errors such as short circuit and open circuit.
In case any of these errors is detected,
engine will work in failure mode, and fault
indicating lamp will go on.
Signal output: this sensor outputs
0.5V

-4.9V DC voltage signals. Rotate the

sensor to test the output signal, which shall
be a continous signal without fluctuation or
interruption.

Installation: allowable tightening torque
for fastening screw is 1.5Nm-2.5Nm.

Troubleshooting: mainly check if there is

short circuit or open circuit on the

connection between 3 lines on senosr and

ECU.

Check to see if there is short circuit, open

circuit or grounding between sensor wire

harnesses.

Throttle position sensor

Throttle position sensor

Circuit diagram of throttle position sensor

Pins:

1 throttle position sensor (ECU 76#)

2 sensor signal ground (ECU 54#)

3 sensor signal (ECU 60#)

Warning: under most circumstances, the
removal of throttle position sensor is not
allowed.

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Maintenance Manual for Chery·Windcloud

Marelli EFI System

3. Coolant Temperature Sensor TF-W

Purpose: this sensor is designed to provide
coolant temperature information. To provide
engine ECU with water temperature signal
used for control of ignition timing and fuel
injection pulse width in startup, idle speed
and normal operation. The main function of
water temperature sensor is to provide
engine with fuel injection pulse width signal
during cold starting. The sensor also sends
signals to control fan operation.
Composition and principle: this sensor is a
thermistor of negative temperature
coefficient (NTC) with resistance value
decreasing with the increasing of coolant
temperature except linear relation. The said
thermistor is installed in a heat-conducting
sleeve. ECU monitors water temperature
variation by converting resistance value of
thermistor into a changing votage through a
bleeder circuit (inner structure of ECU).
Failure diagnosis: When coolant
temperature is higher than allowed upper
limit or lower than lower limit, failure mark
of the knock sensor is set, engine fault
indicating lamp goes on and engine works in
failure mode. In this case ECU controls
ignition and fuel injection according to set
water temperature for failure mode, at the
same time the fan is running at high-speed
mode (normal fan control for system with
fan controlled by a thermal switch).
Limiting data: 2.5±5%KΩ
Installation hint: tightening torque is 15Nm
in maximum.
Hints: the vehicle is equipped with 2 water
temperature sensors, one is single-pin water
temperature sensor, providing the water
temperature gauge with water temperature
signal; the other is double-pin, providing the
engine ECU with water temperature signal.
Caution: the two water temperature sensors
have different resistance values.

Coolant temperature sensor

Water temperature sensor

Circuit diagram of coolant temperature sensor

Pins: this sensor has 3 pins, which can

interchange for use.

1 coolant temperature sensor signal (ECU

54#)
2 sensor signal ground (ECU 62#)
Troubleshooting: mainly check if there is

short circuit or open circuit on the

connection between 2 lines on senosr and

ECU connector.

If there is short circuit, open circuit or

grounding between sensor wire harnesses.
Line grounding or defect grounding is liable
to cause engine water temperature gauge to
indicate excessive temperature.
Check to see if ECU connector is loose.
Make sure the connector is in good
condition, for internal looseness may occur
to ECU connector.

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