Electrical F
Which of the following is a measure of the number of electrons flowing past a given point in 1 second?
Amp
All of the following statements describing the basic principles of electricity are true except:
An atom with more electrons than protons has an overall negative charge and is called a negative ion.
Which of the following is used to designate a reading of 400 megavolts?
400V
All of the following statements are true except:
As technology has developed, usage of wires and cables has reduced.
Tech A says that a battery stores electrical energy in chemical form. Tech B says that a battery creates direct current. Who is correct?
Both A and B
Tech A says that an ohm is a unit of measurement of resistance. Tech B says that high resistance creates heat at the point of resistance in the circuit. Who is correct?
Both A and B
Which category of DMM is the minimum required when working on hybrid vehicles?
CATIII
Which of the following materials is typically used in the construction of semiconductors?
Copper
Tech A says that all vehicles have a specified CCA rating for the battery. Tech B says that reserve capacity indicates how many times the engine can be started by the battery. Who is correct?
Tech A
Tech A says that while soldering wires, apply the solder to the wire opposite the soldering iron. Tech B says that you should heat the wire up until the plastic insulation melts. Who is correct?
Tech A
Tech A says that a parasitic draw is measured in volts. Tech B says that pulling fuses one at a time can help locate a parasitic draw. Who is correct?
Tech B
Tech A says that it is best to use a knife or other type of sharp tool to cut away the insulation when stripping a wire. Tech B says that any issues with wiring are more likely to be with the terminals than with the wires themselves. Who is correct?
Tech B
Tech A says that the rectifier assembly controls the output of the alternator. Tech B says that the alternator output circuit voltage drop must be checked with the charging system under a heavy load. Who is correct?
Tech B
Tech A says that total resistance goes up as more parallel paths are added. Tech B says that total amperage goes up as more parallel paths are added. Who is correct?
Tech B
Tech A says that when a fuse has blown, it just has to be replaced, because it performed its job. Tech B says that when a fuse has blown, the circuit has to be diagnosed because the fuse was probably not the problem. Who is correct?
Tech B
Tech A says that when testing a relay winding with an ohmmeter, it should show the winding is open. Tech B says that the solenoid closes a set of heavy contacts that send current flow to the starter motor. Who is correct?
Tech B
Which of the following precautions should be taken while measuring the resistance in a series circuit using a DMM?
The components should be disconnected from the circuit.
All of the following statements about transistors are correct except:
They are made up of two sections of different polarity.
Excessive bare wire may:
expose the wire to a potential short circuit.
Electromotive force can be best described as the:
force of attraction/repelling which drives the electrons to move along
The type of battery that is most common in automobiles is a:
lead-acid battery.
Alternators have all of the following characteristics except:
lower maximum RPM.
To test the charging system output do all of the following EXCEPT:
manually or automatically load down the battery just enough to obtain the maximum amperage output without pulling battery voltage below 12.0 volts.
DMM is used to measure all of the following in a circuit except:
specific gravity.
If both wires in the twisted pair CANbus need to be repaired, it is best to:
stagger the joints.
What is the main purpose of the fork in starter motor engagement?
It engages the starter drive.
All of the following statements are true except:
Measuring source voltage is accomplished with both meter leads on the positive terminal of the battery.
Which of the following does a battery convert into electrical energy?
Chemical energy
All of the following statements describing an electrical circuit are true except:
Current flows through the fuse into the circuit wires.
Which of the following materials is widely used to build high-speed semiconductors?
Gallium-arsenide
Which side of a circuit starts at the negative side and ends at switch?
Ground side
Tech A says that NTC thermistors alter their resistance value inversely to temperature (as the temperature increases, resistance value decreases). Tech B says that PTC thermistors are used as throttle position sensors. Who is correct?
Tech A
Tech A says that a 12-volt battery has six cells. Tech B says that the more plates a cell in a battery has, the more voltage it creates. Who is correct?
Tech A
Which component in the alternator controls the strength of the magnetic field of the rotating magnet?
Voltage regulator
The device which is used to measure the amount of resistance in a component or a circuit is a(n):
ohmmeter.
Status-of-the charge of a no-maintenance battery can be determined using a(n):
single cell hydrometer float.
Which of the following batteries are most suited for off-road and all-terrain vehicles?
Absorbed glass mat batteries
All of the following statements are true except:
A battery consists of two similar metals.
Which the following tests is performed to determine the capacity and life left in the battery?
Conductance test
Which of the following is the recommended range to be set on a DMM to get the most accurate reading?
Lowest range possible for the value being measured
What is the total resistance for two 2-ohm resistors connected in parallel?
1 ohm
Which of the following is the best and safest method to clean the battery when there is a voltage of more than 0.2 volts on top of the battery?
Clean with baking soda and water mixture
What is the purpose of the diodes in an alternator rectifier?
to transform the alternating current into direct current.
The force with which the positive terminal pulls the free electrons toward it in a circuit is measured in:
volts
Two technicians are discussing scope testing. Tech A says that the vertical axis of the screen shows voltage. Tech B says that the horizontal axis shows time. Who is correct?
Both A and B
Which component slows down the armature when the starter motor is disengaged?
Brake washer
All of the following statements with respect to the operational function of a starter solenoid are true except:
It conducts electricity from the starter motor to the control circuit.
Fiber optic cable has all of the following advantages over a conventional copper cable except:
It is expensive when compared to conventional cables.
Which of the following types of shielding is used in wiring to prevent electromagnetic interference (EMI)?
Mylar tape
All of the following are factors in shortening battery life except:
a moderate external temperature.
Choose the correct statement.
The COM slot is always used for the black lead.
The lead plates of the lead-acid batteries are immersed in:
diluted sulfuric acid solution.
Tech A says that in a series circuit with two resistors of 120 ohms each, the total circuit resistance is 240 ohms. Tech B says that in a parallel circuit with two resistors of 120 ohms each, the total circuit resistance is 240 ohms. Who is correct?
A
Tech A says that if resistance stays the same and voltage goes up, then amperage goes down. Tech B says that if voltage stays the same and resistance goes down, then amperage goes down. Who is correct?
Tech A
When two dissimilar metals are immersed in an acidic liquid, the breakdown of chemicals into charged particles results in a flow of electricity. This principle is used in a(n):
battery
Choose the correct statement.
Semiconductor devices are sensitive to heat and voltage spikes.
What is the most common use of speed control units in vehicles?
To control the speed of the engine
What is the main purpose of the starter system in a vehicle?
To provide a method of rotating the vehicle's internal combustion engine to begin the combustion cycle
Conducting a voltage drop test on the power and ground circuits is best for locating:
high resistance faults.
Which of the following can be fitted to probe leads to reduce the maximum voltage to safe levels for an oscilloscope to measure?
Attenuator
Tech A says that some relays are equipped with a suppression diode in parallel with the winding. Tech B says that some relays are equipped with a resistor in parallel with the winding. Who is correct?
BOTH
A customer complains of a weak horn. Tech A says that the horn is faulty and should be replaced. Tech B says that performing a voltage drop test on the horn circuit is a valid test in this situation. Who is correct?
Both A and B
Tech A says that a twisted pair is two wires, twisted together, that deliver signals between common components. Tech B says that in many cases, wiring diagrams are set up with power on the top of the diagram and ground on the bottom. Who is correct?
Both A and B
Tech A says that electromotive force is also known as voltage. Tech B says that when electrons flow in one direction only, this is DC. Who is correct?
Both A and B
Tech A says that if a 12-volt light has 10 amps flowing through it, it is using 22 watts of electricity. Tech B says that watts are units of electrical power. Who is correct?
Both A and B
Tech A says that lead oxide acts as an insulator on the battery posts and has to be scraped away. Tech B says that current can leak across the dirt on the surface of the battery. Who is correct?
Both A and B
Tech A says that some starters use gear reduction to improve efficiency. Tech B says that a starter converts electrical energy to mechanical energy. Who is correct?
Both A and B
Tech A says that the movement of electrons in a circuit is called current flow. Tech B says that the movement of electrons in a circuit is measured in amps. Who is correct?
Both A and B
Tech A says that the pull-in winding is short-circuited when the solenoid is fully engaged. Tech B says that the starter drive has a built-in one-way clutch. Who is correct?
Both A and B
Tech A says that the specific gravity of the electrolyte can be checked with a hydrometer. Tech B says that the specific gravity of the electrolyte can be checked with a refractometer. Who is correct?
Both A and B
Tech A says that when reading DC voltage on a meter, a "+" before the number means that there is a higher voltage at the red lead than the black lead. Tech B says that a "−" before the number means that there is a lower voltage at the red lead than the black lead. Who is correct?
Both A and B
Tech A says that wiring diagrams are essentially a map of all of the electrical components and their connections. Tech B says that in many cases, each wire in wire harnesses use two colors; the first one is the solid color, and the second one is the stripe. Who is correct?
Both A and B
Which of the following components can be programmed and are an integral part of other electrical components?
Microprocessors
Tech A says that an open circuit typically causes higher current flow, which will blow the fuse. Tech B says that a short to ground can typically be found by checking voltage at different points in the circuit. Who is correct?
Neither A nor B
Tech A says that checking the specific gravity will indicate the battery's cold cranking amps. Tech B says that a battery load test should be performed when the battery is heavily discharged. Who is correct?
Neither A nor B
Tech A says that the stator rotates inside a magnetic field. Tech B says that the rotor is bolted between the two end housings. Who is correct?
Neither A nor B
Tech A says that 18 AWG wire is larger than 12 AWG wire. Tech B says that the larger the diameter of the conductor, the more electrical resistance it has. Who is correct?
Neither A or B
Tech A says that an unintended resistance results in a voltage drop. Tech B says that one of the factors that determines the level of electrical resistance is the weight of the conductor. Who is correct?
Tech A
Tech A says that most hybrid vehicles use the high-voltage electric motor to start the engine. Tech B says that most hybrid engines need to crank over more slowly than regular engines. Who is correct?
Tech A
Tech A says that overcharging can lead to short life of bulbs and other electrical devices. Tech B says that the charging system regulated voltage is checked with maximum load on the battery. Who is correct?
Tech A
Tech A says that some alternator pulleys are designed to freewheel in one direction. Tech B says that the alternator output terminal is connected to one of the slip rings on the rotor. Who is correct?
Tech A
Tech A says that the surface of the battery can be cleaned with baking soda and water. Tech B says that the electrolyte level should be below the top surface of the plates. Who is correct?
Tech A
Tech A says that the voltage regulator controls the strength of the rotor's magnetic field. Tech B says that the voltage regulator is installed between the output terminal of the alternator and the positive terminal of the battery. Who is correct?
Tech A
Tech A says that to read amperage, the meter must be hooked up in series in a circuit. Tech B says that to read amperage at a load, you should place one lead of the ammeter on the input side of the load and the other lead on the output. Who is correct?
Tech A
Tech A says that when checking a voltage drop across an open switch, a measurement of 12 volts is normal. Tech B says that when checking voltage drop across an open switch, a measurement of 12 volts means there are 12 volts on each side of the switch. Who is correct?
Tech A
Tech A says that when disconnecting the battery, the negative terminal should be disconnected first. Tech B says that baking soda and water will remove lead oxide from battery terminals. Who is correct?
Tech A
Tech A says that when measuring available voltage, the common (black) lead should be on a good ground. Tech B says that a resistance reading on a lightbulb requires the DMM to be hooked to each side of the bulb and the switch turned on. Who is correct?
Tech A
Tech A says that when resistance increases, current flow decreases. Tech B says that when voltage decreases, current increases. Who is correct?
Tech A
Tech A says that a relay is a one-way electrical check valve used in alternators to change AC into DC. Tech B says that a relay uses electromagnetism to open or close a switch. Who is correct?
Tech B
Tech A says that a series circuit has only one path for current to flow. Tech B says that a parallel circuit current flows through one resistor before getting to the next resistor. Who is correct?
Tech B
Tech A says that a transistor has a single P-N junction. Tech B says that a transistor is a semiconductor device used as a switch and to amplify currents. Who is correct?
Tech B
Tech A says that a voltage drop of 0.8 volt on the starter ground circuit is within specifications. Tech B says that high starter draw current could be caused by a spun main bearing in the engine. Who is correct?
Tech B
Tech A says that batteries should be charged as fast as possible. Tech B says that the ideal charging rate is the CCA divided by 70. Who is correct?
Tech B
Tech A says that if the specified fuse keeps blowing, it is generally okay to replace it with a larger fuse. Tech B says that a fusible link is one type of circuit protection device. Who is correct?
Tech B
Two technicians are discussing a series circuit with four resistors of various resistances. Tech A says that current flow is different in each resistor. Tech B says that current flow is the same in each resistor. Who is correct?
Tech B
All of the following statements with respect to the operation of a starter solenoid are true except:
The movement of the solenoid windings engages the drive pinion with the flywheel ring gear
The degree to which a material opposes the passage of electrical current through it is called:
resistance
Automotive battery capacity is rated based on all of the following except:
terminal style.
A starter draw test measures:
the amount of current a starter draws during cranking.
