1.
Technician A says a higher than normal voltage drop could indicate high resistance. Technician B says high resistance causes an increase in current flow. Who is correct?
Correct Answer
A. Technician A
Explanation
Technician A is correct. A higher than normal voltage drop can indicate high resistance in a circuit. When there is high resistance, the flow of current is hindered, leading to a higher voltage drop across the resistance. Therefore, Technician A's statement is accurate. Technician B's statement is incorrect because high resistance actually causes a decrease in current flow, not an increase.
2.
An excess of electrons will give the atom a/n:
Correct Answer
B. Negative charge.
Explanation
An excess of electrons will give the atom a negative charge because electrons have a negative charge. When an atom gains extra electrons, the number of negatively charged electrons exceeds the number of positively charged protons in the nucleus, resulting in an overall negative charge for the atom.
3.
Two technicians are discussing voltage. Technician A says that amperage is the amount of electrons flowing in a circuit. Technician B says that voltage is the amount of force in a circuit. Who is correct?
Correct Answer
C. Both Technicians A and B
Explanation
Both Technician A and B are correct. Amperage is indeed the amount of electrons flowing in a circuit, while voltage is the amount of force or energy in a circuit. Amperage measures the current, or the rate of flow of electric charge, while voltage measures the potential difference or the electrical pressure that drives the flow of electrons. Therefore, both technicians have provided accurate descriptions of these electrical concepts.
4.
Technician A says a parasitic draw is when the alternator is charging the battery. Technician B says when preforming a parasitic draw test, you should wait until all the modules have gone to sleep. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. A parasitic draw refers to an abnormal electrical current that continues to flow from the battery even when the vehicle is turned off. This draw can drain the battery over time. To accurately measure the parasitic draw, it is important to wait until all the modules in the vehicle have gone to sleep. This ensures that all electrical systems have shut down and are not contributing to the draw. Therefore, Technician B's statement is correct.
5.
When preforming a battery open circuit voltage test, what voltage indicates a fully charged battery?
Correct Answer
C. 12.6 volts
Explanation
A voltage of 12.6 volts indicates a fully charged battery when performing a battery open circuit voltage test. This voltage level is considered to be the maximum voltage that a fully charged battery can reach.
6.
A voltage drop test is being performed on the output wire of the alternator, between the alternator output wire to the battery positive post. Technician A says that the voltage drop should be approximately 12.0 volts. Technician B says that during the voltage drop test, the engine should be at the specified rpm and the battery loaded down so the alternator puts out maximum current flow. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. During a voltage drop test, the engine should be at the specified rpm and the battery should be loaded down so that the alternator puts out maximum current flow. This is because the purpose of the voltage drop test is to check for any excessive resistance in the circuit. By loading down the battery and increasing the current flow, any potential voltage drops across resistance points in the circuit can be identified. Technician A's statement that the voltage drop should be approximately 12.0 volts is incorrect, as the actual voltage drop will depend on the specific circuit and its components.
7.
Two technicians are discussing a charging system output test. Technician A says that an amp reading substantially below specifications could be caused by open diodes. Technician B says it could be caused by a faulty regulator. Who is correct?
Correct Answer
C. Both Technicians A and B
Explanation
Both Technicians A and B are correct. An amp reading substantially below specifications in a charging system output test can be caused by open diodes or a faulty regulator. Open diodes can prevent the proper flow of current, leading to a lower amp reading. Similarly, a faulty regulator can fail to regulate the charging system properly, resulting in a lower amp reading. Therefore, both Technician A and Technician B are correct in their explanations.
8.
Two technicians are discussing a vehicle's charging system running at 17.2 volts. Technician A says it is normal for newer vehicles to run a higher voltage like that. Technician B says a faulty voltage regulator could cause that condition. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. A vehicle's charging system should typically run at around 13.5 to 14.5 volts. A voltage of 17.2 volts is higher than normal and could indicate a faulty voltage regulator. The voltage regulator controls the output voltage of the alternator and if it is faulty, it can cause the charging system to produce excessive voltage. Therefore, Technician B's statement is accurate.
9.
Two technicians are discussing a starter that clicks once when turning the key to the crank position. Technician A says that it could be caused by worn solenoid contacts. Technician B says it could be caused by an open ignition switch. Who is correct?
Correct Answer
A. Technician A
Explanation
Technician A is correct. A starter that clicks once when turning the key to the crank position could be caused by worn solenoid contacts. The solenoid is responsible for engaging the starter motor when the ignition key is turned. If the contacts in the solenoid become worn, it can result in a single click sound instead of the starter motor engaging and turning the engine over.
10.
Two Technicians are discussing a higher than normal starter draw amperage reading. Technician A says that could be caused by excessive resistance on the starter ground circuit. Technician B says that could be caused by shorted field windings in the starter. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. A higher than normal starter draw amperage reading can be caused by shorted field windings in the starter. Excessive resistance on the starter ground circuit would not cause a higher amperage reading.
11.
Disconnecting which of the following would allow the engine to crank but prevent it from starting?
Correct Answer
D. Ignition system or fuel system.
Explanation
Disconnecting the ignition system or fuel system would prevent the engine from starting. The ignition system is responsible for providing the spark that ignites the fuel in the engine, while the fuel system is responsible for delivering fuel to the engine. If either of these systems is disconnected, the engine will crank but will not be able to start without the necessary spark or fuel.
12.
What is an example open circuit?
Correct Answer
B. A break in the wire
Explanation
An example of an open circuit is a break in the wire. In an open circuit, there is a gap or interruption in the flow of electric current, preventing it from completing the circuit. In this case, the break in the wire disrupts the path for the current to flow, causing the circuit to be open and preventing the electrical devices from functioning properly.
13.
When measuring voltage with a voltmeter, place:
Correct Answer
C. The red lead in the "Volt/Ohms" slot and the black lead in the "Common" slot.
Explanation
When measuring voltage with a voltmeter, the red lead is typically connected to the "Volt/Ohms" slot and the black lead is connected to the "Common" slot. This configuration allows for accurate voltage measurements to be taken. Placing the red lead in the "Amps" slot and the black lead in the "Neg" slot is incorrect because the "Amps" slot is used for measuring current, not voltage. Similarly, placing the red lead in the "Pos" slot and the black lead in the "Neg" slot is incorrect because these slots are typically used for power supply connections, not voltage measurements.
14.
You have a 4 ohm resistor in series with a 12 battery. How many amps will flow through the resistor?
Correct Answer
C. 3 amps
Explanation
The current flowing through a resistor in a series circuit is determined by Ohm's law, which states that current (I) is equal to voltage (V) divided by resistance (R). In this case, the voltage of the battery is 12 volts and the resistance of the resistor is 4 ohms. Therefore, the current flowing through the resistor is 12 volts divided by 4 ohms, which equals 3 amps.
15.
A circuit has 12 volts and a 0.5 ohm resistor. How many amps flow through the resistor?
Correct Answer
D. 24
Explanation
The correct answer is 24. This can be calculated using Ohm's law, which states that the current flowing through a resistor is equal to the voltage across the resistor divided by the resistance. In this case, the voltage is 12 volts and the resistance is 0.5 ohms. Therefore, the current flowing through the resistor is 12 volts divided by 0.5 ohms, which equals 24 amps.
16.
Two technicians are discussing automotive wire. Technician A says that 12 AWG wire carries more current than 8 AWG. Technician B says that as long as they are both made of copper, they will carry the same amount of current. Who is correct?
Correct Answer
D. Neither Technicians A nor B
Explanation
Neither Technician A nor Technician B is correct. The current carrying capacity of a wire is determined by its gauge, with a lower gauge number indicating a larger wire size and higher current carrying capacity. Therefore, 8 AWG wire carries more current than 12 AWG wire. Additionally, while copper is a good conductor of electricity, the current carrying capacity also depends on factors such as wire length, temperature, and insulation.
17.
Two technicians are discussing relays. Technician A says that relays can fail because the relay winding is open. Technician B says relays can fail because the switch contacts can have high resistance. Who is correct?
Correct Answer
C. Both Technicians A and B
Explanation
Both technicians A and B are correct. A relay can fail if the relay winding is open, meaning there is a break in the coil that prevents current from flowing through it. This will prevent the relay from functioning properly. Additionally, the switch contacts in a relay can develop high resistance over time, which can cause the relay to fail. High resistance can lead to arcing, overheating, and poor electrical conductivity, all of which can affect the performance of the relay. Therefore, both of these factors can contribute to relay failure.
18.
Fuses prevent circuit damage by:
Correct Answer
D. Stopping excessive current flow.
Explanation
Fuses are designed to protect electrical circuits from damage caused by excessive current flow. When the current exceeds a certain limit, the fuse melts and breaks the circuit, stopping the flow of current. This prevents the circuit from overheating and potentially causing a fire or damaging the components. Therefore, the correct answer is stopping excessive current flow.
19.
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 side of the load. Who is correct?
Correct Answer
A. Tech A
Explanation
Tech A is correct. To read amperage, the meter must be hooked up in series in a circuit. This means that the meter is connected in line with the current flow, allowing it to measure the current passing through the circuit. Tech B's suggestion of placing one lead of the ammeter on the input side of the load and the other lead on the output side of the load would not accurately measure the amperage in the circuit.
20.
Technician A states that disc brake rotors can be reused as long as the surface is machined smooth. Technician B states that disc brake rotor thickness variation is measured with a micrometer. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. Disc brake rotor thickness variation is indeed measured with a micrometer. This tool is used to measure the thickness of the rotor at multiple points to ensure that it is within the manufacturer's specified tolerance. If the thickness variation exceeds the allowable limit, the rotor may need to be replaced. Technician A's statement about reusing rotors as long as the surface is machined smooth is not accurate because rotor thickness variation is an important factor in determining their usability.
21.
Excessive disc brake rotor thickness variation will cause:
Correct Answer
D. Brake pedal pulsation.
Explanation
Excessive disc brake rotor thickness variation refers to a condition where the rotor is unevenly worn or warped. This can cause the brake pedal to pulsate or vibrate when braking, which is known as brake pedal pulsation. The uneven surface of the rotor causes the brake pads to make uneven contact, resulting in an inconsistent braking force. This can be felt as a pulsating sensation in the brake pedal.
22.
Disc brake rotors can be out of specification in two ways: thickness variation and:
Correct Answer
C. Lateral runout.
Explanation
Disc brake rotors can be out of specification in two ways: thickness variation and lateral runout. Thickness variation refers to uneven thickness across the rotor, which can cause brake pulsation. Lateral runout, on the other hand, refers to the side-to-side movement of the rotor as it rotates. This can result in brake pedal pulsation, steering wheel vibration, and uneven brake pad wear. Therefore, the correct answer is lateral runout.
23.
Air in the brake lines will cause what type of problem?
Correct Answer
B. Spongy brake pedal
Explanation
When there is air in the brake lines, it can cause a spongy brake pedal. This means that when the brake pedal is pressed, it feels soft and lacks the usual firmness. This can result in a longer stopping distance and reduced braking efficiency. The presence of air in the brake lines can lead to a loss of hydraulic pressure, which is necessary for effective braking. Therefore, a spongy brake pedal is a common problem that occurs when there is air in the brake lines.
24.
To perform an internal leak test on a vacuum power booster, let the engine idle and apply the brake pedal with firm pressure. Without moving your foot, shut off the engine and observe the brake pedal for 1 minute. If the power booster is good, what should the brake pedal do?
Correct Answer
D. Hold steady
Explanation
When performing an internal leak test on a vacuum power booster, the brake pedal should hold steady if the power booster is good. This means that the pedal should not sink slowly, pulsate rapidly, or slowly rise. Holding steady indicates that there are no leaks in the power booster and it is functioning properly.
25.
All of the following are properties of DOT 5 brake fluid, EXCEPT:
Correct Answer
C. It absorbs water.
Explanation
DOT 5 brake fluid is known for its silicone-based formula, which makes it less harmful to paint compared to DOT 3 and DOT 4 fluids. However, this type of fluid is not suitable for vehicles equipped with an anti-lock braking system (ABS). Additionally, DOT 5 brake fluid is not hygroscopic, meaning it does not absorb water. Therefore, the correct answer is that it absorbs water.
26.
Technician A says that packing a wheel bearing assembly means smearing some grease around the outside of the bearing. Technician B says that a wheel bearing assembly can be packed with a bearing packer. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. Packing a wheel bearing assembly does not involve smearing grease around the outside of the bearing. Instead, it involves using a bearing packer, which is a tool specifically designed to evenly distribute grease into the bearing. This ensures that the bearing is properly lubricated and reduces the risk of premature wear and failure.
27.
In many rear-wheel drive vehicles, the wheel bearings are lubricated with that also lubricates the differential assembly.
Correct Answer
C. Gear oil
Explanation
In many rear-wheel drive vehicles, the wheel bearings are lubricated with gear oil. Gear oil is a type of lubricant specifically designed to withstand the high temperatures and pressures generated by the gears in the differential assembly. It provides effective lubrication to the wheel bearings, ensuring smooth rotation and reducing friction and wear. Engine oil, automatic transmission fluid, and compressor lube are not suitable for lubricating the wheel bearings as they are not designed to withstand the extreme conditions in the differential assembly.
28.
The amount of friction between two moving faces in contact with each other is expressed as a ration and is called:
Correct Answer
A. The coefficient of friction.
Explanation
The amount of friction between two moving faces in contact with each other is expressed as a ratio and is called the coefficient of friction. This ratio represents the relationship between the force of friction and the normal force between the two surfaces. It is a dimensionless quantity that helps in quantifying the level of friction between the surfaces. The coefficient of friction is an important parameter in various engineering and physics applications as it helps in understanding and predicting the behavior of objects in contact.
29.
All of the following is a part of the hydraulic brake system, EXCEPT:
Correct Answer
D. Parking brake assembly.
Explanation
The hydraulic brake system consists of various components that work together to apply and release the brakes. Brake hoses, disc brake calipers, and wheel cylinders are all important parts of this system as they help in the transfer of hydraulic fluid and the activation of the brakes. However, the parking brake assembly is not a part of the hydraulic brake system. The parking brake is a separate mechanism that is used to hold the vehicle in place when parked, and it is usually operated mechanically rather than hydraulically.
30.
The purpose of a drop center in a wheel is to allow for:
Correct Answer
C. Tire mounting and dismounting.
Explanation
A drop center in a wheel allows for easier tire mounting and dismounting. The drop center is a recessed area in the wheel where the tire bead can be easily pushed down into during installation or pulled up out of during removal. This design feature makes it more convenient and efficient for mechanics or individuals to change tires, as it provides a space for the tire bead to move into, reducing the force required for mounting or dismounting.
31.
Technician A says that all lug nuts must be torqued to specifications. Technician B says that lug nuts should be tightened in a random sequence. Who is correct?
Correct Answer
A. Technician A
Explanation
Technician A is correct. Lug nuts must be torqued to specifications in order to ensure proper and even distribution of force on the wheel. This helps to prevent the wheel from coming loose while driving and ensures the safety of the vehicle. Tightening lug nuts in a random sequence, as suggested by Technician B, can lead to uneven torque and potentially cause the wheel to become loose over time. Therefore, it is important to follow the specified torque sequence when tightening lug nuts.
32.
Technician A says when checking a tire's air pressure, always refer to the tire sidewall information, and inflate the tire to that pressure. Technician B says when checking air pressure, compare it to the specifications on the tire placard usually located on the driver's door, door pillar, or glove compartment lid. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. When checking air pressure, it is important to refer to the specifications on the tire placard, which is usually located on the driver's door, door pillar, or glove compartment lid. This placard provides the recommended air pressure for the specific vehicle, as determined by the manufacturer. The tire sidewall information may provide the maximum allowable pressure for the tire, but it does not necessarily reflect the recommended pressure for the vehicle.
33.
When attempting a repair on a damaged tire, all of the following are true; EXCEPT:
Correct Answer
D. A tire plug by itself is an acceptable repair.
Explanation
When attempting a repair on a damaged tire, all of the given statements are true except for the statement that a tire plug by itself is an acceptable repair. A tire plug is not considered a permanent or reliable repair method for a damaged tire. It is recommended to use a combination of a patch and a plug to ensure a proper and long-lasting repair. A tire plug alone may not adequately seal the puncture and can lead to air leaks or further damage to the tire.
34.
Tech A says that a static imbalance condition is centered within the width of the tire. Tech B says that a dynamic imbalance condition can be anywhere within the width of the tire. Who is correct?
Correct Answer
C. Both Techs A and B
Explanation
Both Techs A and B are correct. Tech A is correct in stating that a static imbalance condition is centered within the width of the tire. This means that the weight distribution is unevenly distributed across the tire's width, causing vibration. Tech B is correct in stating that a dynamic imbalance condition can be anywhere within the width of the tire. This means that the tire may have uneven weight distribution that changes as it rotates, leading to vibration at different points along the tire's width.
35.
All of the following statements about a tire pressure monitoring system are true, EXCEPT:
Correct Answer
C. It can automatically stop a leak in a tire.
Explanation
The given correct answer is that a tire pressure monitoring system (TPMS) cannot automatically stop a leak in a tire. TPMS is designed to monitor the pressure of the tires and alert the driver through a warning light or message if the pressure is low. It is often referred to as TPMS and can be diagnosed with an appropriate scan tool. However, it does not have the capability to automatically stop a leak in a tire.
36.
A green valve stem cap on tires on recent model-year vehicles means that the tires are:
Correct Answer
B. Filled with nitrogen.
Explanation
A green valve stem cap on tires on recent model-year vehicles indicates that the tires are filled with nitrogen. Nitrogen is commonly used in tires due to its ability to maintain tire pressure for a longer period of time compared to regular air. This helps to improve fuel efficiency, increase tire life, and enhance safety on the road.
37.
The aspect ratio of a tire is:
Correct Answer
D. The ration of its height to its width.
Explanation
The aspect ratio of a tire refers to the ratio of its height to its width. This ratio is important as it determines the tire's profile and how it will perform on the road. A higher aspect ratio indicates a taller tire with a larger sidewall, which can provide a smoother ride and better traction. On the other hand, a lower aspect ratio means a shorter tire with a smaller sidewall, which can enhance handling and responsiveness. Therefore, the aspect ratio is a crucial factor in determining the overall performance and characteristics of a tire.
38.
Technician A says some tire pressure monitoring systems (TPMS) have a sensor mounted in each wheel rim. Technician B says some tire pressure monitoring systems use the wheel speed sensors in the ABS system to detect tires with low pressure. Who is correct?
Correct Answer
C. Both Technician A and Technician B
Explanation
Both Technician A and Technician B are correct. Some tire pressure monitoring systems (TPMS) do have a sensor mounted in each wheel rim, while others use the wheel speed sensors in the ABS system to detect tires with low pressure.
39.
Camber is the:
Correct Answer
B. Inward or outward (side to side) vertical tilt of the wheel.
Explanation
The correct answer is "inward or outward (side to side) vertical tilt of the wheel." Camber refers to the angle at which the wheels of a vehicle tilt inward or outward when viewed from the front or rear. This tilt can affect the vehicle's handling and tire wear.
40.
A pre-alignment inspection includes all of the following, EXCEPT:
Correct Answer
D. Removing the front wheels to prepare for adjustment.
Explanation
A pre-alignment inspection is performed to ensure that the vehicle is ready for the alignment process. This includes checking and adjusting the tire air pressure to the specified levels, inspecting and confirming the correct tire size, and removing any heavy items from the trunk or truck bed that could affect the vehicle's weight distribution. However, removing the front wheels to prepare for adjustment is not part of the pre-alignment inspection.
41.
The components that follow the road contours, such as wheels, tires, axles, and outboard brake assemblies are considered:
Correct Answer
C. To be "unsprung weight".
Explanation
The components that follow the road contours, such as wheels, tires, axles, and outboard brake assemblies are considered "unsprung weight" because they are not supported by the suspension system of the vehicle. This weight directly impacts the vehicle's handling and ride quality as it is not absorbed by the suspension, leading to a more rigid and bumpy ride.
42.
The ____________ connect(s) the wheels to the suspension and steering system.
Correct Answer
D. Steering knuckle
Explanation
The steering knuckle is responsible for connecting the wheels to the suspension and steering system. It is a crucial component that allows the wheels to turn and pivot as directed by the driver's steering input. The steering knuckle is typically attached to the upper and lower control arms, and it houses the wheel hub assembly, which includes the wheel bearings and allows the wheel to rotate smoothly. Overall, the steering knuckle plays a vital role in ensuring proper steering and handling of the vehicle.
43.
All of the following about the flexible joints found in the steering linkage are true, EXCEPT:
Correct Answer
B. They can be disassembled, cleaned, and repacked with grease.
Explanation
The given correct answer is "they can be disassembled, cleaned, and repacked with grease." This means that all the statements about the flexible joints found in the steering linkage are true except for this one. The other statements mention that the joints are sometimes equipped with a grease fitting, they are of ball-and-socket design, and they allow movement without looseness or play. However, the statement about disassembling, cleaning, and repacking with grease is not true for these flexible joints.
44.
When the piston moves from bottom dead center (BDC) to top dead center (TDC) or TDC to BDC, it is known as a:
Correct Answer
D. Stroke.
Explanation
When the piston moves from bottom dead center (BDC) to top dead center (TDC) or vice versa, it is referred to as a stroke. A stroke is one complete movement of the piston in an engine cylinder, which includes both the upward and downward motion. This movement is responsible for the intake, compression, power, and exhaust strokes in a four-stroke engine. The other options, cycle, revolution, and bore, do not accurately describe the specific movement of the piston from one dead center position to the other.
45.
Technician A says that in a four-stroke engine, it takes two strokes to complete a cycle. Technician B says that only one of the four strokes delivers power to the crankshaft. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. In a four-stroke engine, it takes four strokes to complete a cycle: intake, compression, power, and exhaust. Only one of these strokes, the power stroke, delivers power to the crankshaft. Technician A is incorrect in stating that it takes only two strokes to complete a cycle.
46.
The ration of the crank gear to the camshaft gear(s) is:
Correct Answer
B. 2:1
Explanation
The ratio of the crank gear to the camshaft gear(s) is 2:1. This means that for every two rotations of the crank gear, the camshaft gear(s) will rotate once. This ratio is commonly used in engines to synchronize the movement of the crankshaft and the camshaft, which is important for proper valve timing and engine performance.
47.
Intake valves in the cylinder head are closed by pressure from the:
Correct Answer
C. Valve springs.
Explanation
Valve springs are responsible for closing the intake valves in the cylinder head. These springs exert pressure on the valves, ensuring that they close tightly and prevent any leakage of air or fuel mixture from the intake manifold into the cylinder. This is crucial for the proper functioning of the engine, as it allows for efficient combustion and power generation.
48.
What does the "W" in 5W30 engine oil stand for?
Correct Answer
A. Winter
Explanation
The "W" in 5W30 engine oil stands for Winter. This indicates the oil's viscosity or thickness at low temperatures. The number before the "W" (5 in this case) represents the oil's viscosity at colder temperatures, while the number after the "W" (30 in this case) represents the viscosity at higher temperatures. The "W" designation ensures that the oil flows properly during cold starts and provides adequate lubrication in winter conditions.
49.
Technician A says that when installing an oil filter, you should tighten it with a filter wrench to prevent it from falling off. Technician B says that oil filters should only be installed by hand. Who is correct?
Correct Answer
B. Technician B
Explanation
Technician B is correct. Oil filters should only be installed by hand because using a filter wrench to tighten it can lead to over-tightening, which can cause damage to the filter or the engine. Hand-tightening ensures a proper seal without risking damage.
50.
When installing a new oil filter, it is a good idea to:
Correct Answer
D. Wipe a small amount of oil on the new filter gasket.
Explanation
When installing a new oil filter, it is recommended to wipe a small amount of oil on the new filter gasket. This helps to ensure a proper seal between the filter and the engine, preventing any oil leaks. The oil on the gasket also helps to lubricate the gasket, making it easier to remove the filter during future oil changes. Applying contact cement, gasket sealer, or installing the rubber gasket dry are not necessary or recommended steps for installing an oil filter.