JAC S2. Engine. Service Manual — part 17

Engine mounting System

Engine Mounting system 231

Hoare Sensor

1. Component Instruction

Camshaft position sensor and crankshaft position sensor are Hoare sensor, working together with signal wheel on camshaft and

crankshaft, signal wheel corresponding to specified position of engine, ECM conforms engine working condition through digital

voltage signal of the sensor, and control one-for-one.

2. Installation Position

Camshaft position sensor is installed in cylinder head nearby
camshaft.

Crankshaft position sensor is installed in cylinder body nearby
crankshaft.

3. Component Circuit Diagram

Pin number

Function

A

Output

B

Grounding

C

Power supply

C

B

A

Item

Standard value

Working temperature:

-40

～ 150 ℃

System input voltage:

5.0V (Supply power by
controller)

Working intermittence:

0.1-1.5mm

Engine mounting System

Engine Mounting system 232

Pin number

Function

A

Signal grounding

B

Signal output

C

Heating
terminal-

D

Heating terminal +

Oxygen Sensor

1. Component Instruction

Oxygen sensor is used to supply information of whether oxygen is excess after

ECM controls closed loop control of fuel quantify by this information, makes three main toxic ingredients in engine exhausting

gas at utmost be transformed and purified in three-way catalyst converter.

Its sensor assembly is a ceramic tube with pore, outside of tube wall is surrounded with engine exhausting gas, inside is connected

to atmosphere. Sensor indirectly calculates pulse width of fuel injection according to oxygen concentration difference of inside and

outside, transmits to ECM, and ECM control fuel injection again. At the same time it detects rear oxygen sensor output data, compares

data of front and rear oxygen sensor in ECM, and monitor whether three-way catalyst converter is working well.

Working voltage of oxygen sensor is 0.1-0.9V, change 5-8 times every 10s; if lower than the frequency value, it indicates sensor

is aging and needs to be replaced, and the sensor can’t be repaired.

2. Installation position

Front (upper) oxygen sensor is installed in exhausting manifold of
three-way catalyst converter.

Rear (lower) oxygen sensor is installed behind three-way catalyst
converter.

3. Component Circuit Diagram

D C B

A

Item

Standard value

Working voltage

0.1-0.9V

Fuel Injector

Engine mounting System

Engine Mounting system 233

1. Component Instruction

Fuel pumped from fuel pump is stored and distributed through fuel pressure guide rail assembly, supply fairly steady pressure

environment for fuel system, make fuel supplying pressure and fuel supplying amount of all cylinders be balanced, and engine running

steadily. Fuel injector injects fuel according to transmitted signal from ECM, and ensure fuel injector amount by opening time of fuel

injector electromagnetic valve.

2. Installation Position

Installed in fuel rail.

3. Component Circuit Diagram

Item

Standard value

Standard resistance value
between two pins

11~16Ω

Knock Sensor

1. Component Instruction

Knock sensor is installed in side of cylinder body, generally between 2

nd

cylinder and 3

rd

cylinder, and it’s in favor of engine

knock balance. ECM outputs knock frequency signal by knock sensor, and then gets through ECM interior filter, and then judges

whether there is knock in engine; when detecting knock signal, ECM will decrease ignition advance angle gradually until there is no

knock, and then recover gradually until to knock edge, thus repeatedly.

2. Installation Position

Installed in cylinder body, between 2

nd

cylinder and 3

rd

cylinder.

3. Component Circuit Diagram

Pin

Function

1

Signal grounding

2

Signal output

Engine mounting System

Engine Mounting system 234

Item

Standard value

Input voltage

11.5~18.0V

Average working current
when keep position

1.0A

Max current

In the condition of 100

％

air-fuel ratio, -40℃,
15.5V, it’s 2.5A

Environment temperature

-40 ～ 150 ℃

Temperature in hood

-40 ～ 150 ℃

Electromagnetic valve
temperature

-10 ～150 ℃

Continuous Variable Cam Phase Regulator and Its Control Valve

1. Component Instruction

Continuous variable cam phase regulator is used to change timing of valve mechanism. It realizes control of valve phase

by continuously regulating phase relationship of camshaft and crankshaft according to requirement of control system.

VVT pressure regulating control valve is a four-way pulse width control electromagnetic valve, which can move in double

directions and it can control oil flow rate by axial direction motion of plunger valve. Engine ECM changes oil flow rate passing to

two sides of rotor vane to control timing and phase position of cam relative to crank by air-fuel ratio of pulse width regulating.

2. Installation Position

Installed in cylinder head in side of generator belt wheel.

3. Component parameter

Working condition of VCP

Working condition of OCV valve

Type

Oil pressure control
electromagnetic valve

Coil impedance

Standard value:
5.6 Ω (-30 ℃)
7.0 Ω (20 ℃)
10.6 Ω (150 ℃)

Required min current of
plunger valve whole stroke

1A

Input voltage (through coil)

Standard value:
13±0.5V, Min:
11.0V, Max:18.0V

Response when starting in
normal input voltage

<50ms When T

Coil

<65oC

Close response

<50ms When T

Coil

<65oC

Engine mounting System

Engine Mounting system 235

Carbon Canister Electromagnetic Valve

1. Component Instruction

Gasoline vapour produced in fuel tank gets into activated carbon canister by pipe, activated carbon canister can absorb gasol ine

molecule in gasoline vapour. The other outlet hose of activated carbon canister connects to engine intake pipe. Carbon canister

electromagnetic valve in middle of hose controls whether the pipe is connected. When engine running, if electromagnetic valve is

open, air gets into from lower part of carbon canister in the influence of vacuum suction in intake pipe, and gets through activated

carbon, gets into engine intake pipe from upper part outlet through hose, and make gasoline molecule absorbed to surface of a ctivated

carbon evaporate again, and then be absorbed into engine to be burnt with air to make the best of fuel; at the same time it can make

activated carbon in carbon canister recover absorbed ability, and won’t lose efficacy due to using too long.

2. Installation Position

Installed in intake manifold bracket.

Engine mounting System

Engine Mounting system 236

Engine Control Module (ECM)

1. System instruction

Delphi MT22.1 engine control system takes MT22.1 engine control module (ECM) as core, its feature is computer close-loop

control, several-points fuel sequence injection, directly ignite with no distributor group and three-way catalytic converter aftertreatment.

ECM MT22.1 uses latest electronic hardware technology, has higher cost performance; hardware uses 16 bits microprocessor, has

enough storage, high calculation speed, can flexibly define I/O input/output port; software uses second control software programmed

by Delphi modularization C language; has all technical specifications that satisfy current Euro-

Ⅳ and OBD emission laws and

regulations required.

1)ECM has the following functions:

· Vehicle main power supply relay control

· Speed density air flow rate method

· Close-loop control several-points sequence fuel injection (including MAP CID pressure judging cylinder)

·Close-loop control several-points sequence fuel injection

· Has different fuel supplying method, return fuel, no return fuel and half no return fuel

· Fuel pump working control

· Directly ignite with no distributor, there is ignition module in ECU, 4 cylinders ignite in order

· Control intake air flow by electronic throttle valve, response quickly, accurately, realize torque control by ECU, increase
reliability

· VVT-i (electronic-control-type intake phase variable cam regulating device) control intake air amount of engine, increase
torque and power

· Knock control

· Carbon canister electromagnetic valve control

· A/C, coolant trunk fan control

· Mileage memory

· Over-voltage protection

· Electronic anti-theft

· CAN-BUS communication connector can communicate with automatic transmission control module or ABS system

· Open, modularization C language program

2. Component Circuit Diagram













3. Pin Definition List of ECM

Pin

Function

Pin

Function

Pin

Function

Pin

Function

1

Ignition coil B driving

(3

rd

cylinder)

2

Power supply grounding

3

Power supply grounding

4

Ignition coil A driving

(1

st

cylinder)

5

ETC supply power

6

1

st

cylinder fuel injector

7

3

rd

cylinder fuel injector

8

2

nd

cylinder fuel injector

9

A/C switch signal

10

Fuel pump relay

11

Spare pin

12

Spare pin

13

Spare pin 1

14

Spare pin

15

Spare pin

16

Spare pin

17

High speed fan

18

Spare pin

19

Spare pin

20

Throttle valve motor-

Engine mounting System

Engine Mounting system 237

2

E

T

C

Cool

water

T

E

M

P

s

ens

or

M

A

0

.0

-

S

P

3

1

0

5

0

.0

-

S

P

3

1

0

8

0

.0

-

0

.0

-

S

P

3

1

0

4

S

P

3

1

0

7

20

21

52

27

49

77

70

46

75

18

61

51

15

59

39

38

21

Throttle valve motor+

22

Spare pin

23

Rear oxygen sensor

heating

24

Front oxygen sensor

heating

25

4

th

cylinder fuel injector

26

Spare pin

27

Throttle valve position

sensor 2

28

Spare pin

29

Spare pin

30

Crankshaft position

sensor signal

31

Spare pin

32

Spare pin

33

Brake signal light

34

Spare pin

35

Power load 1

36

Knock sensor +

37

Knock sensor -

38

CAN low

39

CAN high

40

A/C middle pressure

switch

41

Accelerator pedal

position sensor 1

42

Accelerator pedal

position sensor 2

43

VVT 1

44

Main relay

45

Spare pin

46

Anti-theft request

47

Front oxygen sensor

signal

48

Rear oxygen sensor

signal

49

Coolant temperature

sensor

50

ENS

51

Spare pin

52

Throttle valve position

sensor 1

53

Spare pin

54 Absolute pressure sensor

55

Spare pin

56

Spare pin

57

Spare pin

58

Spare pin

59

Spare pin

60

Compressor

61

Spare pin

62

Ignition coil C driving

(4

th

cylinder)

63

Spare pin

64

Carbon canister

electromagnetic valve

65

Low speed fan

66

5V reference voltage #2

67

Supply power

68

Ignition signal

69

Brake signal

70

5V reference voltage #2

71

Intake temperature

72

Spare pin

73

Oxygen sensor low

signal

74

5V grounding 1

75

KWP2000

communication

76

5V grounding 2

77 Camshaft position sensor 78

Spare pin

79

A/C request signal

80

Vehicle speed signal

81

Ignition coil D driving

(2

nd

cylinder)

90

Oxygen sensor B heating

control

91

Spare pin

92

(Emission) Malfunction

indicating light

Specific pin number refer to wiring harness principle diagram (spare pin is vain pin)

4. P r i n c i p l e D i a g r a m

High configuration vehicle type

IMM

0.5-P/G

1

IMMO/F-5

IMM

IMM

1 0.5-P/G 31

IMM

31 0.5-P/G

0.0-

1

0.5-P/Br

IMMO/F-5

! IMM

0.5-P/Br

EMS2-L/H-2

OBD

û

/H-3

EMS2-L/H-2

ICM1-L/G-4

ICM1-SS/G-4

2

I3_ME

L

0.5-BrBl

L

2

I3_EM

0.5-P/Br 32

33

32 0.5-P/Br

33 0.5-BrBl

0.0-

0.0-

0.0-

4

6

3

0.0-

5

2

EMS2-L/H-2

ICM1-L/G-5

0.5-G/Gr

L

34

34 0.5-G/Gr

B

EMS2-L/H-2

EMS2-L/H-2

ST/GE-SS/D-5

ST/GE/G-5

0.5-W/Br

! CVT

0.5-P/G

! CVT

0.5-Br/R

35

35

11

11

12

12

0.5-W/O

0.5-P/G

0.5-Br/R

0.0-

0.0-

C

BCM1-H/F-7

BCM1-SS/F-7

BCM2-L/C-5

CAN BUS/F-2

SS

I1_EEC

I1_ECE

0.0-

EMS2-L/H-3

0.5-O/V

! SS

CAN BUS/H-3

0.5-O/V

! SS

0.5-O/Gr

13

13

14

14

0.5-O/V

0.5-O/G

0.0-

0.0-

1

3

2

CAN BUS/H-3

CAN BUS/F-4

SS

0.5-O/Gr

I2_EEC

I2_ECE

0.5-O/Gr

0.5-O/Gr

Intake camshaft position sensor

1

1

0.5-O/Gr

V1

Engine mounting System

Engine Mounting system 238

P

edal

a

c

c

el

er

ator

s

ens

o

r

E

1

2

4

3

1

6

5

1

A

bs
ol

ute

pr

es
s

ur

e

and

ai

r

T

E

M

P

s

ens

o

r

E

1

4

E

1

4

2

S

P

3

1

14

S

P

3

1

0

6

S

P

3

1

10

S

P

3

1

0

9

41

74

42

66

54

7

6

71

30

36

37

60

69

33

50

78

35

7

9

4

0

12

1

9

80

34

26

56

4

2

3

6

5

M35

M17

M35

1

CRU

0.5-Y/Bl 9

CRU

9 0.5-Y/Bl 19

19 0.5-Y/Bl

0.5-BlBr

2

2

0.5-BlBr

OUTPUT1

CRU

0.5-Gr/O 8

CRU

8 0.5-Gr/O 18

18 0.5-Gr/O

0.5-Br/G

0.5-Br/G

3

3

0.5-Br/G

GND1

I3_ME

I3_EM

I2_EEC

I2_ECE

Clock Spring

MT

MT

0.5-G/V

4

4

0.5-G/V

V2

0.5-B

GND1/D-6

MT

0.5-Gr/O 7

0.5-G/W

MT

7 0.5-Gr/O 27

IP IGN/G-3

27 0.5-Gr/O

0.5-O/W

5

5

0.5-O/W

OUTPUT2

I3_ME

I3_EM

I1_EEC

I1_ECE

0.5-P/V

6

I2_ECE

6

I2_EEC

0.5-P/V

GND2

Neutral position sensor

0.0-

0.0-

0.0-

0.0-

0.0-

3

4

0.0-

1

2

0.0-

0.0-

0.0-

3

1

2

0.0-

RPM sensor

1 2

Knock sensor

0.0-

0.5-Y/R 6

MT

6 0.5-Y/R

B

A

MT

0.5-Bl/O

I1_ECE

I1_EEC

Clutch Pedal SW

EMS2-L/B-6

IP IGN/G-5

0.5-BrGr 7

7

0.5-BrGr

ABS-H/F-6

ABS-L/F-8

ABS-SS/F-8

0.5-BrBl 8

8

0.5-Y/Bl 23

23

0.5-Br/V 24

24

0.5-BrBl

0.5-Y/Gr

L

0.5-Br/V

ABS-H/A-5

ABS-L/A-5

ABS-SS/A-5

ACU/A-4

EMS2-L/B-7

ABS-L/A-4

0.5-Bl/O 9

9

0.5-Bl/Y 25

25

0.5-Bl/O

0.5-Bl/Y

HI/LO-H/H-3

HI/LO-L/H-3

HI/LO-SS/H-3

AC/A-4

EMS2-L/B-7

0.5-BlBr 26

26

0.5-BlBr

AC/A-5

EMS

0.5-G/R

0.5-G/Y

0.5-Bl/Y

0.5-BlGr

28

29

30

10

I1_ECE

28

29

30

10

I1_EEC

L

0.5-G/R

L

0.5-G/Y

0.5-BlGr

0.5-Bl/Y

CVT

0.5-Bl/Y

EMS2-L/B-8

EMS2-L/B-8

ICM2-L/G-3

EMS2-L/B-8

ICM2-L/G-4

EMS2-L/B-8

EPS-L/A-5

AC/A-5

EMS2-L/B-8

TCU/B-7

Engine mounting System

Engine Mounting system 239

P

edal

a

c

c

el

er

ator

s

ens

o

r

E

1

2

2

4

3

1

6

5

E

T

C

Cool

water

T

E

M

P

s

ens

or

M

1

A

bs
ol

ute

pr

es
s

ur

e

and

ai

r

T

E

M

P

s

ens

o

r

A

E

1

4

E

1

4

2

0

.0

-

S

P

4

1

0

1

0

.0

-

S

P

4

1

0

4

S

P

4

1

0

2

S

P

4

1

0

6

0

.0

-

0

.0

-

S

P

4

1

0

0

S

P

4

1

0

3

S

P

4

1

0

5

20

21

52

27

49

77

70

41

74

42

66

54

7

6

71

30

36

37

60

69

33

50

78

46

75

18

61

51

15

59

56

4

2

3

M35

M35

1

Low configuration vehicle

IMM

0.5-P/G

1

IMMO/F-5

IMM

IMM

1 0.5-P/G 31

IMM

31 0.5-P/G

0.0-

1

IMMO/F-5

0.5-P/Br

! IMM

2

I3_ME

2

I3_EM

0.5-P/Br 32

32 0.5-P/Br

0.0-

0.0-

4

0.5-P/Br

EMS2-H/H-2

OBD

û

/H-3

L

6

0.0-

3

0.5-BrBl

33

EMS2-H/H-2

ICM1-L/G-4

33 0.5-BrBl

0.0-

5

2

ICM1-SS/G-4

L

0.5-G/Gr

34

EMS2-H/H-2

ICM1-L/G-5

34 0.5-G/Gr

B

L

0.5-W/Br

35

ABS-L/A-2

EMS2-H/H-2

35 0.5-W/O

0.0-

C

EMS2-H/H-2

ST/GE-SS/D-5

ST/GE/G-5

EMS2-H/H-3

! CVT

0.5-P/G

! CVT

0.5-Br/R

L

11

12

I1_EEC

11

12

I1_ECE

0.5-P/G

0.5-Br/P

0.0-

0.0-

0.5-Br/R

20

20

ICM1-L/G-2

I2_EEC

I2_ECE

0.0-

0.0-

1

3

2

Intake camshaft position sensor

0.5-O/Gr

0.5-Br/G

0.5-O/Gr

1

1

0.5-BlBr

2

2

0.5-Br/G

3

3

0.5-G/V

4

4

0.5-O/Gr

0.5-BlBr

0.5-Br/G

0.5-G/V

V1

OUTPUT1

GND1

V2

MT

0.5-B

GND1/D-6

MT

0.5-Gr/O

MT

0.5-G/W

7

IP IGN/G-3

MT

7 0.5-Gr/O 27

27 0.5-Gr/O

0.5-O/W

5

5

0.5-P/V

6

6

0.5-O/W

0.5-P/V

OUTPUT2

GND2

I3_ME

I3_EM

I1_EEC

I1_ECE

I2_ECE

I2_EEC

Neutral position sensor

0.0-

0.0-

0.0-

0.0-

0.0-

3

4

0.0-

1

2

0.0-

0.0-

0.0-

3

1

2

0.0-

RPM sensor

1

2

Knock sensor

0.0-

0.5-Y/R 6

MT

6 0.5-Y/R

B

A

MT

0.5-Bl/O

I1_ECE

I1_EEC

Clutch Pedal SW

EMS2-H/B-6

IP IGN/G-5

0.5-BrGr 7

7

0.5-BrGr

ABS-H/F-6

ABS-L/F-8

ABS-SS/F-8

0.5-BrBl 8

8

0.5-BrBl

ABS-H/A-5

ABS-L/A-5

ABS-SS/A-5

0.5-Y/Bl 23

23

0.5-Br/V

24

24

0.5-Y/Gr

L

Engine mounting System

Engine Mounting system 240

S

P

4

2

0

3

35

79

40

12

19

80

34

0.5-Br/V

ACU/A
-4

EMS2-
H/B-7

ABS-
L/A-4

EMS

Engine mounting System

Engine Mounting system 241

Engine mounting System

Engine Mounting system 242

(III)Technical parameters, maintenance parameters

Technical parameters

Items

Maintenance standard value

assembly clearance of Hall sensor

0.5

～ 1.5mm

Standard resistance between two terminals of oil injector

11~16Ω

resistance between two terminals of Canister Purge
Solenoid

19~22Ω

resistance between two terminals of OCV

7~8Ω

Resistance of oil injector solenoid coil

11~16Ω

(IV)Torque parameters

No.

Items

(N·m)

Torque

Remarks

1

Tap bolt of inlet air temperature
pressure sensor

6±0.5

2 Coolant temperature semsor

20±4

3 Fixing bolt of electronic throttle

10±1

4 Fixing bolt of Hall sensor

10±1

5 Front and rear oxygen sensor

35±5

6 Knock sensor bolt

22.5±2.5

7 OCV bolt

6±1

(V)Maintenance precautions

Precautions of electronic control system

Malfunction of any conponents in electronic control system, like sensors, actuators, control circuit, ECM, will

Engine mounting System

Engine Mounting system 243

affect the running of engine. Since ECM can do fault self-diagnosis, so we can connect ECM with computer

monitor to find the reason of fault by reading the fault code or data flow.

In order to prove the reliability of gasoline engine electronic control system, most of components in this

system are designed as sealed, nondecomposable or cannot be repaired after damage. So the main task of

electronic control system maintenance is to find faulted component and change it.

During the maintenance of electronic control system, please pay attention to the following items or they
may cause damage of ECM or controlling components.

1. You can ONLY use digital electric meter to check the electronic control system (for example, digital
multimeter, oscilloscope for vehicle, diagnostic apparatus and etc.).

2. Please use JAC genuine components during maintenance or it cannot guarantee the normal work of
system.

3. You can ONLY use unleaded gasoline during maintenance.

4. Please obey normative maintenance and diagnosis flow to do the service.

5. DO NOT disassemble any components in system during maintenance.

6. During maintenance, please be careful when take out or put down electronic element (ECU, sensors), DO
NOT let them fall down.

7. Please establish the sense of environmental protection, and effectively dispose the waste in maintenance.

8. When ignition switch is on, DO NOT take out or insert ECM harness connector which can avoid electric

elements in system generate induced voltage at the moment of cut off or connect the power which can

damage the ECM.

9. Please connect the ECM harness connector reliably, or it may damage ECM.

10. When remove the battery or use external battery to junp start, you must turn off the ignition switch first

and then do the removal or jump starting. Pay attention to connect the positive and negative poles in right

positions.

11. DO NOT start the engine when battery connector has not been tightened. And DO NOT remove battery

cable when engine is running. Or the charging pressure of engine will be too high to damage elements in

this electronic control system.

Engine mounting System

Engine Mounting system 244

1. While running the engine to check compression pressure of air cylinder, please cut off the power of oil

injector or plug out all connectors of injector, in order to avoid injected oil come into exhaust pipe before

burning which can cause damage of three-way catalyst.

2. When check the ignition system, you can only do arcing check if it's necessary and keep the time as

short as possible, or it may cause a lot of unburned oil get into exhaust pipe to damage the three-way

catalyst.

3. During hot working condition simulation for fault or service work which can cause increasement of
temperature, please make sure the temperature of ECM be under 80 ℃.

4. Please let professional serviceman remove oil pipes and change fuel filter at well-ventilated palce.

5. DO NOT detect input and output signal of components by impaling surface of wires.

Precautions of engine OBD system

ECM is equipped with an OBD (on-board diagnosis) system, and the fault lamp will be on if
there is any fault caused by aging of exhaust system.

1. Before any service anc check, please turn the ignition switch to OFF, and cut off the connection with

battery negative pole. Open circuit or short circuit of relative switches, sensors and solenoids can light the

fault indicating lamp.

2. After service work, please connect and lock the connectors reliably. Loose (unlocked) connectors may
cause open circuit which will light the fault indicating lamp. (Make sure there is no water, lubrication grease,
dirt on connector, and no bend or crack of stitch inside the connectors);

3. After service work, please arrange and fix wirings correctly. If the brackets have interference with wiring, it
may cause short circuit which will light the fault indicating lamp.

4. After service work, please connect the rubber pipes correctly. If they are not well connected, it may cause

fault on EVAP system and injection system which will light the fault indicating lamp.

5. Before deliver the vehicle to customer, please eliminate all useless fault info in ECM (repair is done);

6. You must use 12V battery as power supply.

7. DO NOT cut off the connection with battery when the engine is running.

8. Before connect or cut off the connection of ECM harness, please turn the ignition switch to OFF and cut

off the connection of battery negative pole. Or it may damage ECM, because battery still supplies power to

ECM even when the ignition switch is turned to OFF.

9. Before disassemble components, please turn the ignition switch to OFF and cut off the connection of
battery negative pole.

10. DO NOT disassemble ECM;

11. If any battery cable is cut off, the Memory will back to ECM initial value. ECM will do self-control

according to this initial value. When the battery terminal is cut off, the rotating of engine will change a

little. But it is not a fault. Please do not change components because of this subtle change.

12. When you connect the ECM wiring connectors, please push the lever to the end so that the ECM can be
locked reliably.

13. When insert or pull out the pin connector from ECM, pay attention to not damage the terminal

Engine mounting System

Engine Mounting system 245

(bending or cracked). When you connect the pin connector, please pay attention that the ECM pin terminal

is not bended or cracked.

14. Connect the ECM wiring connectors tightly. Poor connection can cause extremely high voltage on coil
and condenser which will damage ECM.

15. Keep components and wiring of engine electronic control system dry.

16. Even a very small leakage of air inlet system can cause serious fault, so DO NOT change inlet air pressure
sensor randomly.

17. DO NOT wobble or shake camshaft position sensor (phase), and crankshaft position sensor (location);

18. When you use circuit tester to measure ECM, DO NOT let these two gauges touch with each other.

19. Accidental contact of engine electronic control connectors will cause short circuit, and damage ECM
power transistor.

20. When you measure input/ output voltage, please DO NOT use the ECM grounding terminal. Or it may
damage ECM power transistor. Please use other to connect to ground except ECM terminal.

21. If there is no fuel in fuel pipe, DO NOT use fuel pump.

22. Please tighten the fuel hose clamp to specified torque.

23. DO NOT step on accelerator pedal in starting.

24. DO NOT increase the engine speed immediately after starting.

25. DO NOT speed up just before shut down the engine.

26. Please turn off the ignition switch first before cut off wires connected to battery. If cut off the wires

while the engine is running or opening ignition switch, it may cause damage of ECM.

27. Wiring harness between ECM and sensors should use same shielding bond strap with vehicle body to

shield, in order to avoid ignition system interference and radio interference. If the shield wiring harness

does not work, please change it.

28. While checking the charging state of electric generator, DO NOT cut off the battery positive pole which
can avoid the damage of ECM.

29. Whe use external charger to charge the battery, please cut off the battery connection which can avoid
the damage of ECM.

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II、Fault Diagnosis

(I)On-Board Diagnostics

1Instruction

On-Board Diagnostics system (OBD system for short), is intergrated in engine controlling system, and it can

monitor faulted components which may affect exhaust emission and state of engine’s min function. It can

identify, store and show fault information through Malfunction Indicator Light (MIL).

2. I ntroduction of functions

The main functions of this sytem are monitoring, storing fault code, notifying, fail-safe and data outputting.

(1) Monitoring: the main objects this system monitors are sensors, actuators and controlling

process of gasoline engine electronic control system. OBD system keeps monitoring relative signal

of electronic control system during driving, and when a signal goes beyond the set value and

remained for a period, OBD system will make the judgement that the corresponding circuit or

components of this signal has fault.

(2) Restore fault code and noticing function: once the OBD system finds any fault in electronic control

system, the indicator light will be on immediately to remind the driver to send the vehicle for repair

before bigger damage produced.

OBD system can also read the fault and store it as fault code in ECM storage. During service, serviceman can

read the fault code from ECM to find some evidence for locating the fault.

(1) Fail-safe: OBD system will adopt different fail-safe modes for different monitoring objects.

(2) Data storing and outputting: units for ECM to store data are ROM and RAM. Program stored in

ROM is based on refined calculation and experiments. This inherent program will keep comparing

and calculating different signals from sensors while the engine is working, inorder to control the

engine.

All circuits of electronic control system are set specialized diagnostic sockets, just connect ECM decoder with

this socket, you can easily visit ECM storage unit and read stored fault code.

Beside, OBD system can also output data flow which shows working condition of electronic control system
through the diagnostic sockets.

3. Instruction of MIL and controlling strategy

1)MIL: indications for relative components of exhaust system and failure of system. MIL is normally an

indicator light showed on dashboard and is also comply with legislations.

2)Activation of MIL should obey the following items: