10. Figure 34–2 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. Continued CAUTION: The use of a continuity test light is not recommended on any electronic circuit. Because a continuity light contains a battery and applies voltage, it may harm delicate electronic components.
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16. Figure 34–6 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 VW terminal. Continued
17. Figure 34–7 Common abbreviations used on the display face of many digital mutimeters. See the charton Page 342 of your textbook. Continued
18. Figure 34–8 A summary chart indicating what measurement type may be used to test which vehicle system. See the chart on Page 343 of your textbook.
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24. Figure 34–11 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. Continued
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26. Figure 34–12a 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. (a) Manufacturers specify that a high-impedance digital meter be used. When a voltmeter is connected to measure voltage, the meter itself becomes part of the circuit. Continued
27. Figure 34–12b 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. (b) The high internal resistance has little effect on the circuit or component being measured. Continued
28. Figure 34–13 Typical digital multimeter (DMM) set to read DC volts.
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32. Figure 34–15 Using a digital multimeter set to read ohms ( Ω ) to test this light bulb. The meter reads the resistance of the filament.
38. Figure 34–19 Always look at the meter display when a measurement is being made, especially if using an autoranging meter. Continued
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52. Figure 34–21 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.
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57. Figure 34–23 The display on a digital storage oscilloscope (DSO) displays the entire waveform from idle to wide-open throttle and then returns to idle. The display also indicates the maximum reading (4.72V) and the minimum (680 mV or 0.68V). The display does not show anything until the throttle is opened, because the scope has been set up to only start displaying a waveform after a certain voltage level has been reached. This voltage is called the trigger.
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69. Figure 34–25 A pulse train is any electrical signal that turns on and off, or goes high and low in a series of pulses. Igniter and fuel-injector pulses are examples of a pulse train signal. Continued