Automotive Computer Controlled Systems

✍ Scribed by Allan Bonnick

• Publisher: Butterworth-Heinemann
• Year: 2001
• Tongue: English
• Leaves: 266
• Category: Library

✦ Synopsis

'Automotive Computer Controlled Systems' explains the fundamental principles of engineering that lie behind the operation of vehicle electronic systems. Having obtained this knowledge, the reader will be able to make full use of the diagnostic equipment which is currently available. The book builds on the concepts contained in Vehicle Electronic Systems and Fault Diagnosis and gives clear steps to fault diagnosis and subsequent repair of the vehicle's electronic systems. The author discusses electronics only within the context of the vehicle systems under consideration, and thus keeps theory to a minimum. Allan Bonnick has written articles for several transport/vehicle journals and carries out consultancy work for the Institute of Road Transport Engineers. In addition, he has had many years teaching experience and is ideally placed to write this informative guide. * Principles discussed in context avoiding unnecessary theory and maths * Practical step-by-step instructions on fault diagnosis and repair * Liberally illustrated with clear diagrams

✦ Table of Contents

1.1 Common technology......Page 15
1.3.1 THE CONSTANT ENERGY IGNITION SYSTEM......Page 16
1.3.2 DIGITAL (PROGRAMMED) IGNITION SYSTEM......Page 17
1.3.3 DISTRIBUTORLESS IGNITION SYSTEM......Page 20
1.3.4 OPTOELECTRONIC SENSING FOR THE IGNITION SYSTEM......Page 22
1.3.6 ADAPTIVE IGNITION......Page 23
1.4 Computer controlled petrol fuelling systems......Page 24
1.4.1 SINGLE-POINT INJECTION......Page 25
1.4.2 MULTI-POINT INJECTION......Page 27
1.5 Engine management systems (EMS)......Page 31
1.5.1 EXHAUST GAS RECIRCULATION......Page 32
1.6 Anti-lock braking (ABS)......Page 33
1.7 Traction control......Page 36
1.8 Stability control......Page 39
1.9 Air conditioning......Page 41
1.9.1 DEALING WITH AIR CONDITIONING REFRIGERANT......Page 43
1.11 Computer controlled diesel engine management systems......Page 44
1.11.1 SPILL CONTROL......Page 47
1.11.3 IDLE SPEED CONTROL......Page 49
1.13 Review questions......Page 52
2.1 The fundamental parts of a computer......Page 54
2.2 A practical automotive computer system......Page 55
2.3 Principles of operation......Page 58
2.4.1 DATA TRANSFERS......Page 59
2.5 Computer interfaces......Page 60
2.6 Control of output devices......Page 61
2.7 Computer memories......Page 62
2.7.1 READ ONLY MEMORIES......Page 63
2.7.3 OTHER TYPES OF COMPUTER MEMORY......Page 64
2.9 Adaptive operating strategy of the ECM......Page 65
2.10.2 STAR CONNECTED COMPUTERS......Page 66
2.10.3 MESSAGES......Page 67
2.10.4 PROTOCOLS......Page 68
2.11.1 THE PRINCIPLE OF A BUS-BASED VEHICLE SYSTEM......Page 69
2.11.3 ENCODING SERIAL DATA......Page 71
2.12 Prototype network systems......Page 73
2.13 Summary......Page 76
2.14 Review questions......Page 77
3.1 Access to DTCs......Page 79
3.1.1 METHOD 1: THE DASHBOARD LAMP......Page 80
3.1.3 METHOD 3: FAULT CODE READERS AND SCAN TOOLS......Page 84
3.2 Developments in self-diagnosis......Page 92
3.2.2 OBD II......Page 93
3.3 Diagnostic equipment and limitations of DTCs......Page 95
3.4 Review questions......Page 97
4.1 Diagnostic tools that connect to ECM......Page 99
4.2 Breakout boxes......Page 108
4.3 The digital multimeter......Page 109
4.4 Portable flat screen oscilloscopes......Page 110
4.5 Diagnostic tool and oscilloscope combined......Page 111
4.6.1 VACUUM PUMPS AND GAUGES......Page 113
4.9 Sources of diagnostic data......Page 117
4.10.1 PETROL ENGINE EMISSIONS......Page 119
4.10.2 DIESEL ENGINE EMISSIONS......Page 122
4.11 Review questions......Page 124
5.1.1 THE VARIABLE RELUCTANCE TYPE SENSOR......Page 126
5.1.2 HALL EFFECT SENSORS......Page 130
5.2 Optical sensors......Page 132
5.3 Combustion knock sensors......Page 133
5.4 Variable resistance type sensors......Page 135
5.5 Temperature sensors......Page 138
5.6 Ride height control sensor......Page 139
5.7 Manifold absolute pressure (MAP)......Page 140
5.7.1 THE VARIABLE VOLTAGE MAP SENSOR......Page 141
5.7.2 OTHER MAP SENSORS......Page 143
5.8 Exhaust gas oxygen sensors......Page 144
5.8.1 THE VOLTAIC-TYPE EGO SENSOR......Page 146
5.8.2 THE RESISTIVE-TYPE EGO SENSOR......Page 151
5.9 Air flow measurement......Page 152
5.9.1 HOT WIRE MASS AIR FLOW SENSOR (MAF)......Page 156
5.11 Review questions......Page 158
6.1 Actuator operation......Page 160
6.2.2 MULTI-POINT PETROL INJECTION......Page 161
6.3.1 PEAK AND HOLD......Page 163
6.3.2 CONVENTIONAL SWITCHING TO EARTH......Page 164
6.3.3 PULSE WIDTH MODULATED INJECTORS......Page 166
6.4 Exhaust gas recirculation......Page 168
6.5 Petrol engine idle speed control......Page 169
6.5.1 STEPPER MOTOR-OPERATED VALVE......Page 171
6.5.2 SOLENOID-OPERATED VALVE......Page 174
6.7 ABS actuators......Page 175
6.8 A clamping diode......Page 176
6.9 Electronic unit injectors......Page 177
6.10 Review questions......Page 179
7.1 Circuit testing......Page 182
7.2 Vehicle specific details......Page 186
7.3 The 'six-steps' approach......Page 187
7.4 Skills required for effective diagnosis......Page 188
7.5 An approach to fault finding......Page 189
7.6.1 OXYGEN SENSOR......Page 193
7.6.2 KNOCK SENSORS......Page 200
7.6.3 AIR FLOW METERS......Page 201
7.6.4 THROTTLE POSITION SWITCHES......Page 204
7.6.5 A COOLANT TEMPERATURE SENSOR......Page 206
7.6.6 MANIFOLD ABSOLUTE PRESSURE SENSOR (MAP) TESTS......Page 209
7.7.1 TESTS ON DISTRIBUTORLESS IGNITION DIS......Page 212
7.8 Diesel injection......Page 214
7.9 Sensor tests on other systems......Page 216
7.9.1 ABS WHEEL SPEED SENSORS......Page 217
7.9.2 TESTING THE RIDE HEIGHT CONTROL SENSOR......Page 220
7.10 Intermittent faults......Page 221
7.10.1 FLIGHT RECORDER (DATA LOGGER) FUNCTION......Page 222
7.11 Summary......Page 223
7.12 Review questions......Page 224
8.1 Partial and absolute pressures......Page 226
8.2 The piezoelectric effect......Page 227
8.3 Liquid crystal displays......Page 228
8.5.1 THE RTL NOR GATE......Page 230
8.5.2 TRUTH TABLES......Page 231
8.5.3 THE SR (SET, RESET) FLIP-FLOP......Page 232
8.5.4 ANALOGUE TO DIGITAL CONVERSION......Page 235
8.5.5 DIGITAL TO ANALOGUE CONVERSION......Page 236
8.6 OBD II......Page 237
8.6.1 FUEL SYSTEM LEAKAGE......Page 238
8.6.2 SECONDARY AIR INJECTION......Page 239
8.6.4 STANDARDIZED FAULT CODES......Page 240
8.8 Supplementary restraint systems (SRS)......Page 241
8.8.1 HANDLING SRS COMPONENTS......Page 244
8.9 The coded ignition key......Page 245
8.11 Precautions when working with computer controlled systems......Page 246
8.12 Variable capacitance sensor......Page 247
8.13 Optoelectronics......Page 248
8.14 Review questions......Page 249
A.2 Answers to review questions......Page 251
A.3 OBD II standard fault codes......Page 252
Index......Page 263