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Trang 2 HC, O2, N2HCN2O2O2N2HCH2O, CO2, N2Basics about combustion4EMS gasoline 1λ = 1 real air rate equal stoichiometric air rate λ < 1 rich mixture real air rate < stoichiometric air ra

Low price

Low pollution Low noise and

vibrationDrivability

High durability

Development steps of engine control systems

λ = 1 real air rate equal stoichiometric air rate

λ < 1 rich mixture (real air rate < stoichiometric air rate)

λ > 1 lean mixture (real air rate >stoichiometric air rate)

signal processingactuator control

Air Induction System

IG/SW (ON) IG/SW (ST)

MFI Control Relay

Fuel pump check connector Auto fuel cut device (in case of a crash)

Delivery pipe and pressure regulator

To fuel tank

Adjustment screw Conter spring Seal

Return line Inlet

Valve body Diaphragm Control spring

2.5 or 2.9 bar

At 0 vacuum

Fuel pressure Atmospheric Pressure Intake Manifold Pressure 2.5 or 2.9 bar

Fuel pump Fuel filter

Fuel pipe

Fuel pressure regulator

Injectors

Fuel delivery system to be checked for leakage

visibily during maintenance

Vacuum hose to pressure regulator to be

checked during inspection / in case of problems

Supports

Fuel Injectors

Solenoid Resistor

Low Resistance Injector

High Resistance Injector

Caution:

Never apply battery voltage directly across a low resistance injector This will cause injector damage from

solenoid coil overheating

Pencil Beam

Conical (Pintle)

Conical (4H)

Stream

2- Hole

Multi-14

EMS gasoline 1

Air Filter

MAF Throttle Body

TPS Idle Speed Controler

Air Intake ChamberAir induction overview

Intake Valve

Intake air chamber and manifold

Air Intake Chamber

in the case of idle speed problems) Vacuum Signal Ports

Basic adjustment may be required in

the case of idle speed problems

Throttle body

Gear

Drive motor TPS1,2

Return spring

Shaft

Throttle valve ETC – Throttle body

18

EMS gasoline 1

TPS1 TPS2 APS 1, 2

ABS ECM

Throttle motor

Throttle valve Throttle body assembly

Engine

ECM

(TCS Control) CAN Com.

Drive gear ETC block diagram

Variable intake system

ECM

20

EMS gasoline 1

Interference Valve Manifold Valve

Upper tract for cylinders

#1, #3 and #5 Lower tract for cylinders

#2, #4 and #6 Variable intake system

Vacuum hoses to be checked visbily during maintenance

1400 rpm 3950 rpm

TPS = 25 %

Open Closed Open

Open Open Open

Variable intake system

22

EMS gasoline 1

CVVT control

* BDC : Bottom Dead Center

* TDC : Top Dead Center

Injection time shortened

ECM control for leaner mixture

O 2 sensor signal

>0,5 V Rich

mixture Mixture

gets richer

Emission control

The charcoal canister may be replaced during maintenance

Air Flow Sensor

26

EMS gasoline 1

ECM control of Injection duration

Determination of final injection pulse width is the function of a three step process.

Step 2 Corrected Injection Duration Determined (Basic Injection Duration Correction) IAT Correction Warm-up enrichment After-start enrichment Power enrichment Air/Fuel Ratio Feedback Correction Step 3 Final Injection Signal Determined (Voltage Correction)

Intake Air Temperature

Time Lag Injection Signal

Injection Actually Open

Fuel injection correction

Battery voltage correction Power enrichment correction

Intake Air Temperature Correction

Voltage Correction

Actual Injection Duration

Duration of Fuel Injection Signal During Starting

-50 –20 0 5 20 40 80 Coolant Temperature (°C)

MAF/MAP CKP

Corrected Injection Duration IAT, ECT, O2, TPS

Final Injection Duration Voltage Correction

Acceleration and decelleration corrections

Fuel Resume speed

Fuel Cut off speed

Ignition system overview

Knock sensor

Advance and dwell angle control

Without dwell angle control

With dwell angle control

0

Primary current

Ignition Timing

TDC Ignition

IGT Advance Angle

34

EMS gasoline 1

Spark advance strategy

Initial Ignition Timing

Basic ignition advance angle

A/C and Idle

Increased Decreased

Advance Angle 0

Over temperature correction

Idle switch OFF

Engine Knocking Occurs Retard

Advance Engine Knocking Stops

Engine Knocking 0

Retard Angle

ECM

38

EMS gasoline 1

Knock control

Engine management

gasoline 2

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2

EMS Gasoline 2

ECM

Input signal and output signals

Air quantity detection: MAF / MAP / Intake air temp

Electrical load switch / FR terminal

Power steering pressure switch / pressure sensor

Engine coolant temperature sensor

Throttle position sensor / Accelerator position sensor

Crankshaft position sensor / Camshaft position sensor

Ignition switch on / Crank signal / Battery voltage Knock sensor / Ignition failure / Ionic current sensor

Engine oil temperature sensor

Vehicle speed- / Wheel speed- / Accelerator sensor

Inhibitor switch / Neutral switch

AC switch / Triple switch / Pressure transducer

Bus communication / Torque reduction request

Brake switch / clutch switch Barometric pressure sensor Oxygen sensor front / rear Immobilizer Diagnosis output request Injectors / Injector driver Main relay Fuel pump relay Cooling fan relay / PWM module

Check engine lamp Oil control valve

Ac compressor relay EGR solenoid valve

Electronic throttle

Oxygen sensor heater circuit

Variable intake system solenoid

Immobilizer control lamp Bus communication

Ignition coils

G terminal Idle speed actuator

Diagnosis output Purge control solenoid

Crankshaft / Camshaft position sensor

TDC detection slit

No.1 Cylinder TDC detection slit LED

Throttle position sensor

5V Supply

TPS Signal

Ground Idle Signal

TPS

ECM 5V

Power Signal 1

Signal 2 Power

Mass airflow / barometric pressure sensor

Barometric pressure sensor

Hot Wire Type / Hot Film type IAT

Intake Air Mass g/sec

Hybrid assy.

O-ring Housing assy.

Hybrid IC

Sensor element

Heater

Intake Air Thermistor

10

EMS Gasoline 2

Manifold absolute / barometric pressure sensor

Barometric pressure sensor build in ECM

IC

Signal

Perfect Vacuum Chamber

Silicon Chip

IC

High (Rich)

Low (Lean)

Voltage of Oxygen Sensor Signal

Injection +

Volume

-Decreased Increased

Stoichiometric Air/Fuel Ratio

Time

B1,S1 B1,S2

B1,S1 B1,S2

Catalyst Exhaust Flow

450 mV for Zirconia type 2,5 V for Titania type

Oil temperature sensor

Engine coolant temperature sensor

Micro Processor

Reed switch Magnet

Vehicle speed sensor

Wheel sped sensor

Transmission Transaxle

Transmission Transaxle

Transmission Transaxle

Transmission Transaxle

V S

Combination Meter

ABS Control Unit

Combination Meter

A/C switch Dual pressure switch

Triple pressure switch

Inhibitor switch

Ignition switch

Input and output

Air quantity detection: MAF / MAP / Intake air temp

Electrical load switch / FR terminal

Power steering pressure switch / pressure sensor

Engine coolant temperature sensor

Throttle position sensor / Accelerator position sensor

Crankshaft position sensor / Camshaft position sensor

Ignition switch on / Crank signal / Battery voltage

Knock sensor / Ignition failure / Ionic current sensor

Engine oil temperature sensor

Vehicle speed- / Wheel speed- / Accelerator sensor

Inhibitor switch / Neutral switch

AC switch / Triple switch / Pressure transducer

Bus communication / Torque reduction request

Brake switch / clutch switch

Barometric pressure sensor

Oxygen sensor front / rear

Immobilizer

Diagnosis output request

Injectors / Injector driver

Main relay Fuel pump relay Cooling fan relay / PWM module Check engine lamp

Oil control valve

Ac compressor relay EGR solenoid valve Electronic throttle Oxygen sensor heater circuit Variable intake system solenoid Immobilizer control lamp Bus communication

Ignition coils

G terminal Idle speed actuator

Diagnosis output Purge control solenoid

Fuel injector Relays, injector and CVVT control valve

CVVT oil control valve

Fuel pump relay Main relay

Ac compressor relay Etc.

18

EMS Gasoline 2

Idle speed actuator: stepper motor

Pintle Valve

Idle speed actuator: rotary valve

Coil T1

Sensor Signals

+B

ISC1 ISC2

S N S

S

N

N +B

S N

S N

S N

20

EMS Gasoline 2

Radiator Fan : 1EA (PWM control)

If ECT over 115 ℃ , Compressor is Off (ECT hys.7 ℃ )

WTS failure : Duty 90% (Fan : 100%)

ECT : hys 2 ℃ , Vehicle Speed : hys 5Km/h

PWM

A/C A/C pressure Vehicle

speed

Coolant temperature( ℃ ) -30 82 94 96 98 101 103 105 109 115

Middle 1 : 12.0 kgf/㎠ Middle 2 : 15.5 kgf/㎠ (1.0 kgf/㎠= 14.22 psi)

Cooling fan relay / control module

VIS-2 VIS-1

Purge control solenoid

Solenoid valves

VIS solenoid EGR solenoid

M

Control 1

Control 2

ECM TPS

TPS1

TPS2 Power

0V ON

OFF

IGT

Primary Voltage

Ignition Control Circuit

IGF

IGT

ECM

Micro Processor

Data output

Diagnosis code Current data Actuator test Oscilloscope ECM reprogram

*VCI : Vehicle Communication Interface

*VMI : Vehicle Measurement Interface VCI

InputVIN

[ Related Information ]

Case Analysis Symptom Analysis

DTC Analysis Shop / ETM TSB

Scan Function

Warranty Repair History

Engine management 3

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Control modules, logic gates

and reprogramming

Copyright by KIA Motors All rights reserved.

ROM RAM PROM

Output Interface D/A Converter Input Devices

Output Devices

A/D Converter

V 7

6

4 2

1

3 5 6 6 7 6 6 5 3 1 0 0 0 1 3 5

3.2V = 00110101 0V = 00000000 7V = 11111111

System memory

Input Interface A/D Converter

CPU

ROM RAM PROM

Output Interface D/A Converter

Keep Alive RAM

6

Engine management system 3

Structure of the microcomputer

Input/Output Module (I/O)

Voltage

Regulator

Clock Generator

Internal Bus

Analog/Digital Converter

Microprocessor (CPU)

Read Only Memory (ROM)

Random Access Memory (RAM)

Microcontroller

Read Only Memory (ROM)

Random Access Memory (RAM)

Microcontroller Watchdog

Control Module

Arithmetric and Logical Module (ALU) Central Processing Module

Accumulator

8

Engine management system 3

Logic „AND“ gate

A

B

C Inputs Output

Logic Symbol for „AND“ Gate

Semiconductor „AND“ circuit

Equivalent Mechanical circuit

Logic „OR“ gate

Inputs Output

Logic Symbol for „OR“ Gate

Semiconductor „OR“ circuit

Equivalent Mechanical circuit

Switch A

Switch B

10

Engine management system 3

Logic „NOT“ gate

Inputs Output

Logic Symbol for „NOT“ Gate

Semiconductor „NOT“ circuit

Equivalent Mechanical circuit Truth table for „NOT“ Gate

A Inputs

Switch A Relay

Logic „NAND“ gate

Engine management system 3

Logic „XOR“ gate

5V 0

0 1 1

1

5V 1

0 0 1

ECT

Failure conditions

Failure condition

NOT 1 NOT 2

NOT 1 NOT 2

No failure condition

14

Engine management system 3

Example: DTC P0116 Engine coolant temperature circuit range/performance

DTC Strategy • Rationality check • Open in signal circuit

• Open in ground circuit

• Faulty Thermostat

• Faulty IATS

• Faulty ECM

Enable Conditions • Ignition On

Threshold Value • Error is recognized when the rising time of the

coolant temperature up to 40°C(113°F) is deviated from below data after the engine was started -40° (-113°F) @ 65535sec -20°C (-4°F)

@750sec 5.5°C @ 572sec 40°C (113°F) @ 20sec

Diagnostic Time • 0sec

25°C when cranking

• Engine performance is reduced over 120°C

• Radiator cooling fan and A/C condenser fan are operated

• Air conditioning system deactivated

• Water heater deactivated

History of ECM development

I/O

Input/

Output

ROM Read Only Memory CPU Central Processing Module RAM Random Access Memory

Stage 1

OBD Software stored in ROM

Programs and data´s inside one unit

Software update possible by replacing the ROM

Reprogramming only by manufacturer

I/O

Input/

Output

EPROM Electrical Programmable Read Only Memory CPU Central Processing Module RAM Random Access Memory

Stage 2

Software stored in EPROM

Program and/or data inside installed, partly or completely reprogrammable

ROM further developed to EPROM

Repair by replacing EPROM

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Engine management system 3

Software stored in EEPROM

Allocation into firm program areas and flexible data areas

I/O

Input/

Output

EEPROM II Elec Erasable Programmable Read Only Memory CPU Central Processing Module RAM Random Access Memory

Stage 5

Software stored in EEPROM

Program and data area are flexible

Software update by using flash technique

Items required for reprogramming

Reprograming Softwaredat or nrd file

Power supply

PC with Software Windows 98, 2000, XP or NT

PC Scan Software Download or EMT program

HI-SCAN Pro with DLC cable (16-pin)

ECM Reprograming Kit09910-01000AdaptorECM 8P, 10PTCU 2P,8P,10PReprogram Card

RS-232C cable

18

Engine management system 3

Bosch / Siemens ECM

MELCO ECM and/or TCM

Reprograming KIt Software download / upload procedure

PC-SACN program

On board diagnostic system

on gasoline and diesel engines

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20

Engine management system 3

On Board Diagnostic system (OBD)

Malfunction Indicator Lamp (MIL)

Diagnostic Trouble Codes (DTC))

Diagnostic Monitor of:

Major Input Sensors

Fuel Metering

EGR System Function

Circuits monitored for opens and shorts Generation 1

„Continous Monitor“ and

„Once per Trip“

EGR Flow Monitoring

Evaporative Flow Monitoring

Secondary Air Monitoring

New MIL Illumination Rules

Standardization

Diagnostic Trouble Codes

Serial Data Stream

22

Engine management system 3

EOBD

„Continuous Monitor“ and

„Once per Trip“

Diagnostic Trouble Codes

Serial Data Stream

Scan Tool Comprehensive Component Monitoring

European On Board Diagnostic (EOBD)

OBD regulations Japan

Diagnostic Trouble Codes

Serial Data Stream

Comprehensive Component

Monitoring

24

Engine management system 3

Malfunction Indicator Lamp (MIL) and Data Link Connector (DLC)

The Malfunction Indicator Lamp indicates two different failures:

Case 1:

When the ignition is switched ON and during cranking the MIL illuminates for

a function control, the MIL extinguishes once the engine is running at idle

When an emission related failure has been detected for the third time, the MIL will be illuminated and a DTC is stored in the ECM

Case 2:

Blinking of the MIL during driving indicates danger of catalytic converter damage Reducing the engine load will stop flashing and the MIL will be steady ON

Data Link Connector (DLC)

4 - Ground

7 - K Line

15 - L Line

16 - +12V

4 = Additional exhaut gas monitoring

5 = Cruise Control / Idle speed control

6 = Input/ Output signal, Control units

Engine management system 3

Freeze frame data

OBD-II / EOBD relevant DTC´s

Data 1: Related to DTC P0102 Data 2: Related to DTC P0051

Engine stop Drive and warm - up cycle

Idle test mode

ECM

Crankshaft Position-Camshaft Position correlation

HO2S Heater circuit (low/high)

Mass Air Flow circuit (low/high) Intake Air Temperature circuit (low/high)

Throttle Position Sensor circuit (low/high) Engine Coolant Temperature circuit

(low/high)

Engine Oil temperature circuit (low/high) O2 Sensor circuit low/high voltage

Injector circuit (low/high) Idle Air Control system (idle speed

low/high)

Camshaft Position sensor circuit (malfunction)

O2 Sensor pumping current circuit

Crankshaft Position Sensor circuit Reference Voltage circuit

Evap Emission System O2 Pumping current Trim circuit

System Voltage

Internal Control Module check

MIL Control circuit

Idle speed actuator circuit

CAN Communication

30

Engine management system 3

Short driving test mode

Permissible Range by the MAF table value

according to the TPS signal and engine rpm

Measured MAF value

High Temperature and/or High altitude limit

Cold temperature limit

Out of range (time/counter)

t

V

Fault Code Description Fault Detection

P0101 Mass Air Flow Circuit Range/Performance 