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

ECM Harness Connector EN01

1

2

Cylinder No.4 Fuel Injector Harness 

Connector EN14

FE02-5074b

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect cylinder No.4 fuel injector wiring harness
connector EN14.

(c)

Disconnect ECM harness connector EN01.

(d)

Measure resistance between cylinder No.4 fuel injector
wiring harness connector EN14 terminal No.1 and ECM
harness connector terminal No.64. Check whether the circuit
is open. If there is no open circuit, repair the faulty part.

(e)

Measure resistance between cylinder No.4 fuel injector
wiring harness connector EN14 terminal No.1 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 cylinder No.4 fuel injector wiring
harness connector EN14 terminal No.1 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 EN14 (1) and EN01
(64)

Less than 1 Ω

Resistance Between EN14 (1) and a
Reliable Ground

10 kΩ or higher

Voltage Between EN14 (1) and a Reliable
Ground

0 V

Execute next step as per normal.

Next

Step 7

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 8

Replace ECM.

Next

Step 9

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.

(f)

Read control system DTC code again to confirm that the
system has no DTC code.

Engine

Control System JL4G18-D

2-143

No

Intermittent Fault. Refer to 

2.2.7.3

 

Intermittent

Fault Check

Yes

Step 10

Diagnostic completed.

5. Repair Instructions:

Replace the fuel injector. Refer to 

2.2.8.2

 

Fuel Injector Replacement

.

2.2.7.28 DTC P0300-P0304

1. DTC Descriptor:

DTC

P0300

Multi-Cylinder Misfire

DTC

P0301

Cylinder No.1 Misfire

DTC

P0302

Cylinder No.2 Misfire

DTC

P0303

Cylinder No.3 Misfire

DTC

P0304

Cylinder No.4 Misfire

The engine control module (ECM) uses information from the crankshaft position (CKP) sensor and the camshaft position (CMP)
sensors to determine when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder
ECM is able to detect individual misfire events. When a misfire happens, unburnt mixture will be discharged into the exhaust system
and burnt in the exhaust system. A misfire rate that is high enough can cause 3-way catalytic converter damage. The malfunction
indicator lamp (MIL) will ash ON and OFF when the conditions for catalytic converter damage are present. A DTC will be set.

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Control System JL4G18-D

Engine

2. DTC Code Set Up and Removal Conditions:

DTC Code

DTC Detection Strategy

Conditions For Setting The DTC

(Control Strategy)

Fault Locations

P0300
P0301
P0302
P0303
P0304

1. A Misfire Rate Sufficient to

Cause Damage to Catalytic
Converters

2. A Misfire Rate Sufficient to

Cause the Emission
Deterioration

3. Doubtful Error

1. Each Cylinder Catalytic

Converter Damage Related
Misfire Counters.

2. Catalytic Converter Damage

Misfire Rate More Than 4.5%
-20%.

3. Four Emissions Related All

Cylinder Misfire Counts In One
Driving Cycle.

4. Misfire Rate Causing Emission

Deterioration More Than 3.0%.

5. After Starting Each Cylinder

Emission Related Misfire
Counts During a Count Cycle.

6. Undetected Bad Circuit.

7. Fuel Control Inactivated.

8. Torque Intervention Inactivated.

9. Engine speed is greater than

600 rpm and less than 5,000
rpm.

10. Intake air temperature is greater

than -30°C (-22 ºF).

1. Connector Loose or Poor

Connection

2. Vacuum Tube Hose Broken or

Loose

3. Ignition System

4. Fuel Injectors

5. Fuel Pressure

6. Intake Air Pressure Sensor

7. Engine Coolant Temperature

Sensor

8. Cylinder Compression Pressure

9. Valve Clearance and Timing

10. Evaporative Emission Control

System

11. Purged Crankcase Ventilation

System

12. Intake System

13. Poor Exhaust System

Ventilation

14. ECM

Engine

Control System JL4G18-D

2-145

3. Schematic:

Ignition System

01

IF30

From Battery

Main Relay

1,4 Cylinder Ignition Coil

2,3 Cylinder Ignition Coil

Engine 

Control 

Module

Ignition Switch IG1

FE02-5075b

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Control System JL4G18-D

Engine