Chery A11. Manual — part 157

Maintenance Manual for Chery·Windcloud

Marelli EFI System

repair at maintenance station so as to avoid the embarrassment of breaking down on highway
or outdoors. Once failure is identified disappeared, the use of normal data will be restored.

(6). Failure Alarm
Some vehicles equipped with MARELLI system have fault indicating lamps. In case failure
occurs with relevant failure mark being set on some important parts such as ECU, manifold
absolute pressure sensor, throttle position sensor, coolant temperature sensor, knock sensor,
oxygen sensor, phase sensor, injector and two driver stages of idle speed actuator stepper
motor, carbon canister control valve and fan relay, ECU will alarm by lighting up fault
indicating lamp until the said failure mark restores.

(7). Failure Readout
Failure information record can be called up from electronic control unit through scanner. If
failure involves the function of proportion regulator of fuel/air mixture, the engine shall
operate at least 4 minutes to read failure information record.

Connection of Scanner
This system adopts “K” wire communication protocol, locate diagnostic interface at fire wall
of engine compartment with a three-pin connector connecting the said connector and
three-pin plug of the scanner so as to enter engine diagnostic system.

(8). Clearance of Failure Information Record

After elimination of failure, failure information record in memorizer shall be cleared.
When ignition is switched on, in case a failure occurs but dose no continue to the end of
stabilization time, the failure information will not be recorded.
 When the value of frequency counter Hz reaches 0, the failure information record of failure
memory will be removed automatically.
Use scanner to remove failure information record by selecting the command of “Clear failure
memory”.
 Unplug ECU connection or pull out accumulator wires, and clear failure information record
in external RAM.

(9). Failure Identification:
Failure information record is obtained via the aforesaid means with only the rough part of
failure occurrence found. For the reason causing a failure information may be electrical
element breakdown (for example: sensor, actuator or ECU); may be wire having open circuit
or short circuit to ground or accumulator anode; and may be even mechanical failure.
Failure is an internal error, its external exhibition is various symptoms. If a symptom is found,
first check with scanner to see if there is any failure information record, and eliminate
relevant failure as per failure information, and then troubleshoot according to engine
symptom.

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Maintenance Manual for Chery·Windcloud

Marelli EFI System

Failure: too low circuit voltage of intake pressure sensor

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “ON”.

Go to next step

Yes

Go to Step 5

2

Check Intake Pressure in data stream to see if it is
around 101kpa (specific value is related to site
elevation and air pressure).

No

Go to next step

Yes

Go to Step 5

3

Unplug intake pressure sensor connector from wire
harness and check the voltage between Pin 3 and
Pin 1 (i.e. between reference power supply and
signal grounding) of the connector to see if it is
around 5V.

No

Go to next step

Yes

Repair or
replace wire
harness

4

Check respectively connections between Pin 54 of
ECU and Pin 1 of sensor connector, Pin 75 of ECU
and Pin 3 of sensor connector, Pin 68 of ECU and
Pin 4 of sensor connector to see if short circuit
occurs.

No

Go to next step

Yes

Diagnosis
Instruction

5

Start engine and idle it. Slowly step down
accelerating pedal to dead position and observe
value of Intake Pressure on scanner, and it does not
vary much; quickly step down accelerating pedal to
dead position, the instant increase of value of Intake
Pressure reaches 90kpa or more.

No Replace

sensor

Yes

Diagnosis
Instruction

6

Start engine and idle it. Observe value of Coolant
Temperature, it increases along with coolant
temperature.

No Replace

sensor

Failure: too high indication of engine coolant temperature sensor

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “ON”.

Go to next step

Yes

Go to Step 6

2

Check Coolant Temperature in data stream to see if
it is equivalent to engine temperature (specific value
is related to engine temperature at that very
moment)
Note: -40℃ value shown constantly may indicate
open circuit.

No

Go to next step

3

Unplug coolant temperature sensor connector from
wire harness and check the resistance value between

Yes

Go to next step

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Maintenance Manual for Chery·Windcloud

Marelli EFI System

wire harness and check the resistance value between
Pin 1 and Pin 2 with a multimeter to see if it
corresponds with the temperature (refer to
corresponding chapter of this manual for details,
around 2.5K ohm at normal temperature).

No Replace

sensor

Yes

Go to Step 6

4

Unplug coolant temperature sensor connector from
wire harness and check the voltage between Pin 1
and Pin 2 with a multimeter to see if it is around 5V.

No

Go to next step

Yes

Repair or
replace wire
harness

5

Check respectively the connections between Pin 54
of ECU and Pin 1 of sensor connector, Pin 62 of
ECU and Pin 2 of sensor connector to see if they are
short circuit to ground.

No

Go to next step

Yes

Diagnosis
Instruction

6

Start engine and idle it. Observe value of Coolant
Temperature, it increases along with coolant
temperature.

No Replace

sensor

Failure: too low circuit voltage of throttle position sensor

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “ON”.

Go to next step

Yes

Go to next step

2

Check Throttle Absolute Opening in data stream to
see if it is 4%-10% (or the output voltage around
0.6V).

No

Go to Step 5

Yes

Go to next step

3

Slowly step down accelerating pedal to dead
position and observe Throttle Absolute Opening in
data stream to see if it increases to 85-95% along
with opening of throttle.

No

Go to Step 5

Yes Replace

sensor

4

Repeat Step 3 and check Throttle Absolute Opening
in data stream to see if it jumps when changing
(open circuit in TPS).

No

Go to next step

Yes

Repair or
replace wire
harness

5

Unplug throttle position sensor connector from wire
harness, and respectively check the connections
between Pin 54 of ECU and Pin 1 of sensor
connector, Pin 60 of ECU and Pin 2 of sensor
connector, Pin 76 of ECU and Pin 3 of sensor
connector to see if they are short circuit to ground.

No

Go to next step

Yes Replace

sensor

6

Check the voltage between Pin 1 and Pin 2 of
sensor connector with a multimeter to see if it is
around 5V.

No

Diagnosis
Instruction

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Maintenance Manual for Chery·Windcloud

Marelli EFI System

Failure: too high circuit voltage of throttle position sensor

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “ON”.

Go to next step

Yes

Go to next step

2

Check Throttle Absolute Opening in data stream to
see if it is 4%-10% (depends on specific car model). No

Go to Step 5

Yes

Go to next step

3

Slowly step down accelerating pedal to dead
position and observe Throttle Absolute Opening in
data stream to see if it increases to 85-95% (depends
on specific car model) along with opening of
throttle.

No

Go to Step 5

Yes Replace

sensor

4

Repeat Step 3 and check Throttle Absolute Opening
in data stream to see if it jumps when changing.

No

Go to next step

Yes

Repair or
replace wire
harness

5

Unplug throttle position sensor connector from wire
harness, and respectively check the connections
between Pin 54 of ECU and Pin 1 of sensor
connector, Pin 60 of ECU and Pin 2 of sensor
connector, Pin 76 of ECU and Pin 3 of sensor
connector to see if open or short circuit occurs.

No

Go to next step

Yes Replace

sensor

6

Check the voltage between Pin 1 and Pin 2 of
sensor connector with a multimeter to see if it is
around 5V (standard voltage of water temperature
sensor).

No

Diagnosis
Instruction

Failure: signal circuit error of upstream oxygen sensor

Step Operation

Result Solution

1

Connect scanner and commutator, and then turn
ignition switch to “ON”.

Go to next step

Yes

Diagnosis
Instruction

2

Start engine and idle it until coolant temperature is
normal. Observe Oxygen Sensor Voltage to see if
the indication quickly changes between
100mV-900mV (at least 5 changes within 10
seconds).

No

Go to next step

Yes

Repair or
replace wire
harness

3

Check respectively the connections between Pin 20
of ECU and Pin A of sensor connector, Pin 9 of
ECU and Pin B of sensor connector (two thin wires
on ECU wire harness, the two thick wires are
heating coils) to see if they are short circuit to
ground.

No

Go to next step

4

A. Check intake system for severe air leakage;
B. Check injectors for blockage;

Yes

Repair as per
diagnosis

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