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