Transcript Figure 1.1 A funnel is one way to visualize the diagnostic

Figure 5.1 A 12-volt test light is attached to a good ground while probing for power.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
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Figure 5.2 A test light can be used to locate an open in a circuit. Note that the test light is grounded at a different
location than the circuit itself.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.3 Self-powered test lights contain a battery, clamp, and probe. This type of test light should not be used on
any computer-controlled circuits because the applied voltage can damage delicate electronic components or circuits.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.4 High-impedance test light. An LED test light can be easily made using low-cost components and an old ink
pen. With the 470 ohm resistor in series with the LED, this tester only draws 0.025 ampere (25 milliamperes) from the
circuit being tested. This low current draw helps assure the technician that the circuit or component being tested will not
be damaged by excessive current flow.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.5 A logic probe connected to the vehicle battery and relay used to check for power, ground, or a pulse.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.6 Typical digital multimeter. The black meter lead always is placed in the COM terminal. Except when
measuring the current in amperes, the red meter test lead remains in the V terminal.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.7 Common abbreviations used on the display face of many digital multimeters.(Courtesy of Fluke
Corporation)
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.8 A summary chart indicating what measurement type may be used to test which vehicle system.(Courtesy of
Fluke Corporation)
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.9 A typical autoranging digital multimeter automatically selects the proper scale to read the voltage being
tested. The scale selected is usually displayed on the meter face. (a) Note that the display indicates “4,” meaning that
this range can read up to 4 volts. (b) The range is now set to the 40 volt scale, meaning that the meter can read up to
40 volts on the scale. Any reading above this level will cause the meter to reset to a higher scale. If not set on
autoranging, the meter display would indicate OL if a reading exceeds the limit of the scale selected.(Courtesy of Fluke
Corporation)
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.10 Typical digital multimeter (DMM) set to read DC volts.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.11 Using a digital multimeter set to read ohms (Ω) to test this light bulb.The meter reads the resistance of the
filament.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.12 Typical digital multimeter showing OL (over limit) on the readout with the ohms (Ω) unit selected. This
usually means that the unit being measured is open (infinity resistance) and has no continuity.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.13 This chart can be used to convert from one preface to another.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.14 Many digital multimeters can have the display indicate zero to compensate for test lead resistance.(1)
Connect leads in the VΩ and COM meter terminals.(2) Select the Ω scale.(3) Touch the two meter leads together.(4)
Push the “zero” or “relative” button on the meter.(5) The meter display will now indicate zero ohms of
resistance.(Courtesy of Fluke Corporation)
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.15 In this digital multimeter set to read DC amperes, note that the red lead is placed in the far left-hand
socket of the meter. The meter is displaying the current flow (4.18A) through the electric fuel pump on this General
Motors 3800 V6 engine.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.16 An inductive ammeter clamp is used with all starting and charging testers to measure the current flow
through the battery cables.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
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Figure 5.17 A typical mini clamp-on-type digital multimeter. This meter is capable of measuring alternating current
(AC) and direct current (DC) without requiring that the circuit be disconnected to install the meter in series. The jaws are
simply placed over the wire and current flow through the circuit is displayed.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.18 An AC and DC current clamp such as the one shown can be used with a regular digital multimeter. The
amp probe contains a separate battery and electronic circuit that converts the amperage reading into a millivolt (mV)
signal.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
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Figure 5.19 Note the blade-type fuse holder soldered in series with one of the meter leads. A 10 amp fuse helps
protect the internal meter fuse (if equipped) and the meter itself from damage that might result from excessive current
flow if accidentally used incorrectly.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.20
A summary of the test meter hookup
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
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Figure 5.21 Always look at the meter display when a measurement is being made, especially if using an autoranging
meter.(Courtesy of Fluke Corporation)
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.22 When reading AC voltage signals, a true RMS meter (such as a Fluke 87) provides a different reading
than an average responding meter (such as Fluke 88).The only place this difference is important is when a reading is to
be compared with a specification. (Courtesy of Fluke Corporation)
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.23 This meter display shows 052.2 AC volts. Notice that the zero beside the 5 indicates that the meter can
read over 100 volts AC with a resolution of 0.1 volt.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.24 Be sure to only use a meter that is CAT III rated when taking electrical voltage measurements on a
hybrid vehicle.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
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Figure 5.25 Always use meter leads that are CAT III rated on a meter that is also CAT III rated to maintain the
protection needed when working on hybrid vehicles.
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.
Figure 5.26
technician.
A typical fused jumper lead. Fused jumper (text) leads can be purchased or can be made by the
Advanced Engine Performance Diagnosis, Fourth Edition
James D. Halderman
Copyright ©2009 by Pearson Higher Education, Inc.
Upper Saddle River, New Jersey 07458
All rights reserved.