13,12,17 electrical

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Between _____ and _____ pole pieces or "claws" are found in the rotor of heavy vehicle alternators.

12,16

Which of the following charging system set points are accurate?

13.5 to 14.6 volts

In diesel engines, what is the most common ratio between the flywheel ring gear and pinion gear?

20:1

An ohmmeter display indicates the resistance of a circuit is 3.2 k. How many ohms of resistance does this equal?

3,200 ohms

What is the minimum life expectancy for a modern starter?

4 years with 7,000 start cycles

When battery voltage drops below __________ volts while cranking, the voltage-sensing relay will typically open-circuit the starter relay circuit.

7.2

Which of the following test instruments is the best to measure electrical signals from multiple wires connecting to an ECU?

A break-out box

When you have overcharged batteries, the cause could be __________.

A defective voltage regulator

Which of the following is not correct concerning gel cell batteries?

A fully charged gel cell battery has an open-circuit voltage of at least 12.55 volts.

Which of the following is correct concerning valve-regulated lead-acid batteries (VRLA)?

All of the choices are correct.

Which of the following statements is correct concerning battery selection?

All of the choices are correct.

Which of the following is correct concerning preventative maintenance practices?

Alternator surfaces should be cleaned until they are free of accumulations of dirt, grease, and dust. Air passages need to be unobstructed to allow air to easily pass through Mounting brackets should be inspected for loose bolts and to allow correct belt alignment. all are correct

Technician A says that a fully charged battery should have an open-circuit voltage of 12.25 volts. Technician B says that if the battery has been recently charged, a light load applied to the battery for a few minutes will remove a surface charge.

B

Technician A says multimeters are electrical measuring instruments combining functions of at least voltage, resistance, and amperage measurement into a single compact instrument. Technician B says digital multimeters are the most common category of multimeters and provide numerical displays of electrical data. Who is correct?

Both Technician A and B

Technician A says that during charging and discharging, water in the electrolyte is broken apart into its constituent hydrogen and oxygen in a process called electrolysis. Technician B says if battery electrolyte is too low, the plates dry out, and the increased acid concentration of electrolyte permanently damages the grids. Who is correct?

Both a and b

Which of the following multimeter arrangements is best used to check for an open circuit inside an ~3' long (1 m) ground cable connecting the frame to the engine block?

Disconnect the cable and check its continuity

In powered circuits, which of the following are placed around a conductor and are used to measure amperage?

Inductive amp clamps

Which of the following is not correct concerning lithium-ion batteries?

Lithium-ion batteries have liquid electrolyte similar to lead-acid batteries.

Which of the following statements about the starting/cranking system is correct?

On ECM starting systems, the ECM controls the operation of a relay to energize the starter circuit. Data supplied by other onboard network modules, along with control algorithms in the module, determine when and for how long the starter will crank. A control circuit determines when and if the cranking circuit will function. all of the above

What is the correct procedure to measure amperage in a DC circuit?

Open the circuit and place the meter in series with an energized circuit

What type of starter can be identified by an offset drive housing to the motor housing?

Reduction gear drive

Technician A says that a popular type of LED test light is battery powered and has two LEDs—one red and the other green. Technician B says that the LED light changes brightness depending on the circuit's voltage. Who is correct?

Technician A

Technician A says that before using a digital multimeter, one of the first things to check is whether its shunts or fuses are in place and functioning. Technician B says shunts do not operate like fuses and do not have a maximum rating. Who is correct?

Technician A

An auto-ranging meter is set to measure resistance and the positive test lead is placed in the meters only amp probe port. There is infinite resistance displayed by the meter. What does it indicate?

The meter shunt is open

A test light illuminates when connected between a chassis ground and the grounded metal case of a blower motor that is switched on. Which of the following best describes the circuit's condition?

The motor has an open ground circuit.

Which of the following switches would be an over crank protection switch?

Thermal protection

Which is the best reason for using a vehicle communication interface adapter?

To enable a PC or laptop to communicate with a vehicle network

__________ connected in parallel to the battery provide a high initial current to the starter to speed up the armature rotation.

Ultra-capacitors

Under which of the following conditions will the test light lamp illuminate when the lead wire is clipped and connected to a good chassis ground?

When the test light probe is touching the battery-ignition supply side of a blown fuse

Which of the following statements is correct concerning deep cycle-deep discharge batteries?

all are correct

Which of the following statements about the commutator is correct?

all of the above

In a(n) __________, the magnetic field is created by the rotor, which rotates within the stationary stator windings to generate electricity

alternator

What is the only rotating component of the starter?

armatures

Technician A says that a fully charged 12-volt battery is 12.00 volts. Technician B says that connecting cells together in series allows batteries to be produced in a variety of output voltage. Who is correct?

b

Which of the following is NOT a main component of the armature?

body

Technician A says that the demand for advanced battery technology in commercial vehicles is growing. Technician B says that not only do the increasingly popular hybrid electric vehicles require advanced batteries, but heavy-duty commercial vehicles also have a greater need for electrical storage capacity to run accessories. Who is correct?

both

Technician A says that hybrid electric vehicles are not commonplace in industrial settings, but are likely to be in the future. Technician B says that heavy equipment, particularly diesel-powered equipment, uses multiple batteries connected in series or parallel to produce adequate starting current. Who is correct?

both a and b

Technician A says that the primary difference between deep cycle batteries and SLI is the thickness of the plates. Technician B says that deeply discharging SLI batteries dramatically shortens their service life. Who is correct?

both a and b

Technician A says you should never create a low-resistance connection or short across the battery terminals. Technician B says to always wear protective clothing such as rubber gloves and goggles or full-face shields when handling batteries. Who is correct?

both a and b

Which of the following statements is correct concerning separator plates?

both a and b

Technician A says testing starter motor current draw is the best indicator of overall cranking system performance. Technician B says starter motors can be tested in two ways: on vehicle or off vehicle. Who is correct?

both tech a and b

Technician A says that in addition to providing the electrical energy for cranking the engine, the battery has the function of storing an electrical charge in chemical form. Technician B says the battery acts as an electrical dampening device for variations in voltage or voltage spikes. Who is correct?

both tech a and b

Technician A says that today, the average 12-volt electrical system loads for a late-model highway tractor add up to 150 amps at peak with an 84-amp average. Technician B says that both DC generators and alternators produce electricity by relative movement of conductors in a magnetic field. Who is correct?

both tech a and b

Technician A says vehicles fitted with self-exciting alternators may require the engine rpm to be briefly increased after every start-up to initiate charging. Technician B says that using self-exciting alternators eliminates the need for a separate circuit from the key switch to the alternator and simplifies chassis wiring. Who is correct?

both tech a and b

Worn bushing or bearings will cause excessive __________.

current draw

A(n) __________ voltage regulator uses a pulse-width-modulated signal to control the magnetic field strength

digital

What can cause premature failures of diodes?

heat

Both DC generators and alternators produce electricity by relative movement of conductors in a(n) __________.

magnetic field

Starter motors can be tested in two ways. The off-vehicle test is called a(n) __________ test.

no-load

Several pairs of diodes, referred to as the __________ bridge, have the job of converting AC current to usable DC current.

rectifier

In an alternator, which of the following is a rotating electromagnet that provides the magnetic field to induce voltage and current in the stator?

rotor

Which of the following is NOT a component of a starter?

rotor

Which of the following common electric motors develop the highest torque and are used as starter motors?

series

A(n) __________ belt is a type of multi-rib belt that is long enough to drive multiple accessories.

serpentine

Voltage regulation for 12-volt systems will establish a maximum charging voltage, known as the __________.

set point

Direct-drive starters transfer torque directly to the __________ gear.

spur-gear

An alternator loose belt will slip and cause __________.

under charging

Diodes rectify the stator's AC current into DC. Although this happens, a small AC voltage still appears at the alternator's output terminal is referred to a what?

AC ripple

Which of the following circuits prevents the starter motor from operating if the engine is running?

Automatic disengagement lockout

Which of the following is correct concerning types and classification of batteries?

Both A and B

What is connected in series with a major component or wiring harness to an ECM?

Break-out box

A test light is used to __________.

Determine the presence or absence of current

The alternator converts mechanical energy into electrical energy by __________.

Electromagnetic induction

If the solenoid clicks or chatters, it might indicate __________.

Loose or corroded battery terminals

If current output does not rise after full fielding, it may indicate that __________.

The rectifier bridge is shorted, open, or grounded

How is the strength of a magnetic field sensed when measuring DC amperage?

Using a Hall Effect sensor

One of the characteristics of low- or no-maintenance batteries is __________.

lower water usage

Field coils are connected in series with the armature windings through the __________.

stater brushes

Technician A says that a smart charger is a battery charger in which microprocessors control charging rates and times. Technician B says that AGM state of charge can be tested with a battery hydrometer. Who is correct?

tech a

Technician A says that batteries should be the starting point when diagnosing complaints such as hard starting, slow cranking, or no start. Technician B says that dirt on top of the battery does not cause premature self-discharge of the battery. Who is correct?

tech a

Technician A says that if electrolyte is lost due to spillage, then the battery should be topped up with electrolyte. Technician B says that if electrolyte level is lost through evaporation, then tap water should be added. Who is correct?

tech a

Technician A says the stator is made of loops of coiled wire wrapped around a slotted metal alternator frame. Technician B says the regulator is made of loops of coiled wire wrapped around a slotted metal alternator frame. Who is correct?

tech a

Technician A says there is only one way to test a relay. Technician B says solenoids are tested by measuring the voltage drop between the battery terminal and motor terminal. Who is correct?

tech b


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