Geely EC718, EC718RV, EC715, EC715RV. Manual part — 51

Yes

Intermittent Fault. Refer to

2.2.7.3

Intermittent

Fault Check

No

Step 6

Test the oxygen sensor signal.

(a)

If the voltage data is consistently below 0.45 V (mixture too
lean), carry out steps as following:

•

Spray proper amount of propane gas into the intake.

•

Check whether the Post-Catalytic oxygen sensor voltage
data has a significant change, as it will cause signal
voltage rise rapidly.

(b)

If the voltage data is consistently above 0.45 V (mixture too
rich), carry out steps as following:

•

Put gear into Neutral.

•

Apply hand brake.

•

Press the accelerator pedal so that the engine speed
suddenly increases to 4,000 rpm and then quickly release
the accelerator pedal.

•

Repeat the previous step more than 3 times.

•

Check whether the Post-Catalytic oxygen sensor voltage
data has a significant change, as it will cause signal
voltage decrease rapidly.

During the test, the oxygen sensor signal voltage should have
significant changes.

Does voltage have a significant change?

Yes

Check the cause for engine Air-Fuel ratio too
lean/too rich. Refer to

2.2.7.4

Fault Symptom

Table

.

No

Step 7

Check whether there are other control system DTC codes.

(a)

Connect scan tool to the datalink connector.

(b)

Turn the ignition switch to "ON" position.

(c)

Press the scan tool power button.

(d)

Select the following menu items: Engine/Read DTC codes.

(e)

Read DTC codes.

Results:

DTC Codes Shown

To Step

DTC code other than P0136, P0137, P0138,
P0140, P2270, P2271DTC, P0136, P0137,
P0138, P0140, P2270, P2271

No

Engine

Control System JL4G18-D

2-119

DTC Codes Shown

To Step

P0136, P0137, P0138, P0140, P2270,
P2271DTC, P0136, P0137, P0138, P0140,
P2270, P2271

Yes

No

Refer to

2.2.7.11

DTC Code Index

Yes

Step 8

Inspect the exhaust system seal.

(a)

Check the three-way catalytic converter appearance (signs
of excessive heat, gasket missing, etc.).

(b)

Check whether the exhaust pipe is intact and whether gasket
is intact.

No

Replace the damaged parts. Go to step 16

Step 9

Measure oxygen sensor signal circuit.

FE02-5047b

1

2

3

4

Post-Catalytic Oxygen Sensor

Harness Connector EN03

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect the oxygen sensor wiring harness connector
EN03.

(c)

Turn the ignition switch to "ON" position.

(d)

Measure voltage between oxygen sensor wiring harness
connector EN03 terminal No.4 and a reliable ground.

Standard Voltage: 0.35-0.5 V

(e)

Connect the oxygen sensor wiring harness connector EN03.

Is voltage the specified value?

No

Go to step 12

Yes

Step 10

Measure the post-catalytic oxygen sensor ground circuit.

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Control System JL4G18-D

Engine

FE02-5048b

1

2

3

4

Post-Catalytic Oxygen Sensor

Harness Connector EN03

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect the oxygen sensor wiring harness connector
EN03.

(c)

Turn the ignition switch to "ON" position.

(d)

Measure resistance between Post-Catalytic oxygen sensor
connector EN03 terminal No.3 and a reliable ground.

Standard Resistance: Less than 1 Ω

(e)

Connect the post-catalytic oxygen sensor wiring harness
connector EN03.

Is resistance the specified value?

No

Go to step 13

Yes

Step 11

Replace the post-catalytic oxygen sensor.

Next

Go to step 16

Step 12

Check the post-catalytic oxygen sensor signal circuit.

FE02-5049b

1

2

3

4

Post-Catalytic Oxygen Sensor

Harness Connector EN03

ECM Harness Connector EN01

1

3

5

7

8

6

4

2

9

10

11

12

13

23

24

25

26

27

28

29

30

37

51

52

53

54

55

56

57

58

59

60

61

62

63

64

38

39

40

41

42

43

44

45

46

47

48

49

50

31

32

33

34

35

36

14

15

16

17

18

19

20

21

22

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect the post-catalytic oxygen sensor wiring harness
connector EN03.

(c)

Disconnect ECM harness connector EN01.

(d)

Measure resistance between post-catalytic oxygen sensor
wiring harness connector EN03 terminal No.4 and ECM
harness connector terminal No.29. Check whether the circuit
is open. If there is no open circuit, repair the faulty part.

(e)

Measure resistance between post-catalytic oxygen sensor
wiring harness connector EN03 terminal No.4 and a reliable
ground. Check whether the circuit is short to ground. If there
is no short circuit, repair the faulty part.

(f)

Measure voltage between post-catalytic oxygen sensor
wiring harness connector EN03 terminal No.4 and a reliable
ground. Check whether the circuit is short to power supply. If
there is no short circuit, repair the faulty part.

Test Items

Standard Value

Resistance Between EN03 (4) and EN01
(29)

Less than 1 Ω

Resistance Between EN03 (4) and a
Reliable Ground

10 kΩ or higher

Voltage Between EN03 (4) and a Reliable
Ground

0 V

Normal

Go to step 16

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Control System JL4G18-D

2-121

Step 13

Check oxygen sensor ground circuit.

FE02-5050b

1

2

3

4

Post-Catalytic Oxygen Sensor

Harness Connector EN03

ECM Harness Connector EN01

1

3

5

7

8

6

4

2

9

10

11

12

13

23

24

25

26

27

28

29

30

37

51

52

53

54

55

56

57

58

59

60

61

62

63

64

38

39

40

41

42

43

44

45

46

47

48

49

50

31

32

33

34

35

36

14

15

16

17

18

19

20

21

22

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect the oxygen sensor wiring harness connector
EN03.

(c)

Disconnect ECM harness connector EN01.

(d)

Measure resistance between post-catalytic oxygen sensor
wiring harness connector EN03 terminal No.3 and ECM
harness connector terminal No.39. Check whether the circuit
is open. If there is no open circuit, repair the faulty part.

(e)

Measure resistance between post-catalytic oxygen sensor
wiring harness connector EN03 terminal No.3 and a reliable
ground. Check whether the circuit is short to ground. If there
is no short circuit, repair the faulty part.

(f)

Measure voltage between post-catalytic oxygen sensor
wiring harness connector EN03 terminal No.3 and a reliable
ground. Check whether the circuit is short to power supply. If
there is no short circuit, repair the faulty part.

Test Items

Standard Value

Resistance Between EN03 (3) and EN01 (39)

Less than 1 Ω

Resistance Between EN03 (3) and a Reliable
Ground

10 kΩ or higher

Voltage Between EN03 (3) and a Reliable
Ground

0 V

Execute next step as per normal.

Next

Step 14

Check ECM power supply circuit.

(a)

Check whether ECM power supply circuit is normal.

(b)

Check whether ECM ground circuit is normal.

No

Repair the faulty part.

Yes

Step 15

Replace ECM.

Next

Step 16

Use scan tool to confirm whether the DTC code is stored again.

(a)

Connect scan tool to the datalink connector.

(b)

Turn the ignition switch to "ON" position.

(c)

Clear DTC code.

(d)

Start and run the engine at idle speed to warm up the engine
for at least 5 min.

(e)

Road test the vehicle for at least 10 min.

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