Руководство по диагностике электрических схем Toyota (EN)

ELECTRICAL CIRCUIT DIAGNOSIS Course 623 Technician Handbook © 2014 Toyota Motor Sales, U.S.A., Inc. TOYOTA Technical Training All rights reserved. This book may not be reproduced or copied, in whole or in part by any means, without the written permission of Toyota Motor Sales, U.S.A., Inc. Revision Date: December 15, 2014

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Table of Contents 623 Electrical Circuit Diagnosis Objectives Course Map ........................................................................................... a Final Student Performances .................................................................. c 623 Electrical Circuit Diagnosis Course Menu ........................................................................................ 3 Section 1: Section 1 Topics ................................................................................... 5 Introduction ...........................................................................................

6 Attributes of Electricity .......................................................................... 7 Voltage ................................................................................................. 8 Current .................................................................................................. 9 Electrical Principles Effects of Current Flow .................................................................... 10 Resistance .......................................................................................... 11 Resistance Factors .........................................................................

12 Component Resistance .................................................................. 13 Loads .......................................................................................... 13 Ohm’s Law .......................................................................................... 14 Current vs. Resistance ................................................................... 15 Calculating Volts, Amps, or Ohms .................................................. 16 Examples .................................................................................... 16 Section 2: Measuring Section 2 Topics ..................................................................................

17 Meter Functions .................................................................................. 18 Digital Volt-Ohmmeter (DVOM) .......................................................... 18 Electricity DVOM Components ....................................................................... 19 Mode Selector ................................................................................ 20 Display ............................................................................................ 21 Unit Modifiers .................................................................................. 22 Over-Limit Reading .........................................................................

23 Auto Range Feature ....................................................................... 24 Manual Range ................................................................................. 25 Input Jacks ..................................................................................... 26 Measuring Voltage .............................................................................. 27 Source Voltage ............................................................................... 28 Available Voltage ............................................................................ 29 Open Circuit Voltage .......................................................................

30 Voltage Drop ................................................................................... 31 Converting Voltage Values ............................................................. 32 Measuring Current .............................................................................. 35 Maximum Current Capacity ............................................................ 35 Using a DVOM ................................................................................ 36 Converting Amperage Values ......................................................... 37 Electromagnetism ...........................................................................

38 Inductive Current Probes ................................................................ 39 Technical Training i

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Table of Contents 623 Electrical Circuit Diagnosis Measuring Resistance ......................................................................... 42 Using a DVOM ................................................................................ 43 Other Ohmmeter Functions ............................................................ 43 Converting Resistance Values ....................................................... 44 Common Mistakes in Resistance Measuring ................................. 46 Diode Check .......................................................................................

49 Power ................................................................................................. 51 Section 3: Section 3 Topics ................................................................................. 53 Circuit Components ............................................................................ 54 Electrical Circuits Electrical Symbols .......................................................................... 55 Glossary of Terms and Symbols .................................................... 56 Over-current Protection Devices ....................................................

57 Blade Fuses ................................................................................ 58 Control Devices .............................................................................. 59 Diodes ............................................................................................ 60 Resistors ......................................................................................... 61 Fixed Resistor Values ................................................................. 62 Circuit Types ....................................................................................... 63 Series Circuits ....................................................................................

64 Key Features .................................................................................. 64 Applying Ohm’s Law ....................................................................... 65 Voltage Drop ................................................................................... 66 Available Voltage ............................................................................ 67 Predicting Available Voltage ........................................................... 68 Current ............................................................................................ 69 Resistance ......................................................................................

70 Example ...................................................................................... 70 Troubleshooting Using Ohm’s Law ................................................. 77 Open Circuit .................................................................................... 78 Finding an Open Circuit .................................................................. 79 Split-Half Method ............................................................................ 80 Continuity Testing ........................................................................... 81 Short Circuit ....................................................................................

82 Isolating a Short Circuit .............................................................. 82 Short to Ground .............................................................................. 82 Isolating a Short to Ground ......................................................... 83 Parallel Circuits ................................................................................... 84 Key Features .................................................................................. 84 Applying Ohm’s Law ....................................................................... 85 Current Flow ...................................................................................

86 Voltage Measurement .................................................................... 87 Resistance Measurement ............................................................... 88 Current Measurement ..................................................................... 89 Troubleshooting .............................................................................. 90 ii Technical Training

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Table of Contents 623 Electrical Circuit Diagnosis Series-Parallel Circuits ....................................................................... 95 Key Features .................................................................................. 95 Applying Ohm’s Law ....................................................................... 96 Voltage ........................................................................................... 97 Wiring Diagram ................................................................................. 103 Circuit Connections ..........................................................................

104 Load Control ..................................................................................... 105 Power-side Controlled Circuit ....................................................... 105 Ground-side Controlled Circuit ..................................................... 106 Section 4: Inductors Section 4 Topics ............................................................................... 111 Inductors ........................................................................................... 112 Electromagnetism ......................................................................... 112 A Simple Electromagnet ...............................................................

113 Applications of Electromagnetism ................................................ 114 Inductor Coil Control Devices ........................................................... 115 Voltage Spikes .............................................................................. 115 Suppression Diode/Resistor ......................................................... 115 Ignition Coil ....................................................................................... 116 Relay ................................................................................................ 117 Different Types of Relays .................................................................

118 Transistors and Solid State Relays .................................................. 119 Relay Location .............................................................................. 120 Relay Checks ............................................................................... 121 DVOM Limitations ..................................................................... 121 Inductors Controlled by Electronic Components .............................. 122 Section 5: Wiring, Terminal Section 5 Topics ............................................................................... 133 Conductors .......................................................................................

134 and Connector Repairs Insulated (Power-Side) Conductors .............................................. 134 Ground Paths ................................................................................... 135 System Polarity ............................................................................. 135 Harnesses ........................................................................................ 136 Wire Insulation .................................................................................. 137 Aluminum Wire Harness ...................................................................

138 Painted Wire Harness ....................................................................... 139 SRS Harness Components .............................................................. 140 Hybrid High-Voltage Circuits ............................................................ 141 Connectors ....................................................................................... 142 Excessive Terminal Spread ...................................................... 143 Replacing Connectors ...................................................................... 144 Checking Connectors & Terminals ...............................................

143 Different Number of Terminals ..................................................... 144 Different Type Terminals .............................................................. 144 Different Connector Shape ........................................................... 145 Technical Training i

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