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ASE (Entry level technician prep) -
Electrical A6 52 Review Questions
During an output test using the full-field method, a 100-ampere alternator with an integral regulator produces 60 amperes. The cause of the low alternator output could be:
A)a shortened diode in the alternator
B)a broken brush lead wire in the alternator.
C)an open circuit in the voltage regulator.
D)a defective alternator capacitor. - ✔ ✔ Answer A is correct! A shorted diode in a gneerator will typically cause the amperage output to be about one-third less than normal.
In a courtesty light circuit with insulated side door jamb switches, the courtesy lights are completely inoperative. The courtesy light fuse is not blown. The cause of the problem could be:
A) an open circuit in one door jamb switch.
B)an open circuit between the fuse and the door jamb switches.
C)a grounded circuit in one of the door jamb switches.
D)a grounded circuit between the door jamb switches and the bulbs. - ✔ ✔ Answer B is correct! None of the courtesy lights work. The problem must be in that part of the circuit that affects the entire circuit.
Technician A states that a loose serpentine alternative drive belt might lead to overcharging. Technician B states that undersized wiring between the battery and alternator might cause undercharging. Who is correct?
A. Technician A
B. Technician B
C. Both technicians
D. Neither technician - ✔ ✔ Correct answer B - Tech A is incorrect because undercharging is the result of a slipping belt. Tech B is right because the undersize wiring leads to undercharging. This is caused by higher resistance.
Technician A states that a short circuit to ground in a circuit decreases resistance. Technician B states that a short circuit increases current flow. Who is correct?
A. Technician A
B. Technician B
C. Both technicians
D. Neither technician - ✔ ✔ Correct answer C - Both technicians are correct. There's little or no resistance with a short to ground. It's also true that the current flow increases when resistance decreases.
The battery discharges overnight continually. Once the battery is replaced, a drain test is done. The multimeter reading below indicates a parasitic drain. Which of these statements is true?
A
A. 35A of current is indicated
B. This number is unacceptable
A car comes in the shop with a no crank and no sound from the solenoid complaint. The technician turns on the headlights and moves the ignition to the "start" position. The brightness of the headlights stays the same and the complaint is verified. All of the following could be the cause of the problem EXCEPT:
A) an undercharged battery.
B) a faulty clutch switch.
C) a bad starter.
D) an open in the starter circuit. - ✔ ✔ Answer A is correct! An undercharged battery probably would not allow the headlights to be bright in the first place. Also, if the starter circuit were okay, the light would get very dim when the ingition was turned to start. This would happen even though the starter and solenoid could not work because of the low voltage.
A circuit breaker is removed from a functioning power seat circuit, and an ohm-meter is connected to the circuit breaker terminals. Technician A says the ohmmeter should provide an infinite reading if the circuit breaker is satisfactory. Technician B says the ohmmeter current may cause the circuit breaker to open. Who is right?
A) A only
B)B only
C)Both A and B
D)Neither A nor B - ✔ ✔ Answer D is correct! An infinite reading on an ohmmeter indicates there is an open. A good circuit breaker is closed until high current flows through it, then it is open. A good circuit breaker will have zero resistance.
A customer complains that the engine will not turn over. Technician A says to first check if the engine will turn over by turning the crankshaft pulley nut. Technician B says to check the battery condition first. Who is right?
A) A only
B) B only
C) Both A and B
D) Neither A nor B - ✔ ✔ Answer B is correct! Normally, there are other indications for a seized engine being the caused of a no-crank condition. Although Technician A is correct by wanting to verify that the engine is or is not seized by rotating It with a large wrench, this should not be done first. The first thing to do when facing a no-crank situation is to check the battery.
A radio has a whining noise that increases with engine speed. When the alternator field wire is disconnected, the noise stops. All of these defects may be the cause of the problem EXCEPT:
A) a defective stator.
B) a defective diode.
C)a defective capacitor.
D)an open field winding. - ✔ ✔ Answer D is correct! This problem would tend to decrease the chance of radio noise because the alternator (a major source of noise) would not work. A defective alternator will usually cause a whining noise.
A six-way power seat moves vertically at the front and rear, but there is no horizontal seat movement in the figure. All of these defects may be the cause of the problem EXCEPT:
A)a newspaper jammed in the seat track mechanism.
B)an open circuit between the switch and the horizontal motor.
C)an open circuit in the circuit from the switch assembly to ground.
D)burned contacts in the horizontal seat switch. - ✔ ✔ Answer C is correct! The only choice that would not affect horizontal movement is C. An open in the ground circuit would affect the total
B)excessive resistance in the bulb ground circuit.
C)improper bulb handling.
D)cracked lamp cover or housing. - ✔ ✔ Answer B is correct! Three of the answers (A, C, and D) correctly state conditions that would cause premature composite bulb failure. A high charging rate will cause the bulbs to burn brighter and hotter than normal, leading to premature failure.
All of the following statements about using a lab scope for diagnosis are correct EXCEPT:
A) An upward movement of the trace means the voltage has increased and a downward movement means the voltage has decreased.
B)The size and clarity of the trace is dependent on the cleanness of the connection and the component or circuit being tested.
C)A flat waveform means the voltage is staying at that level.
D)As the trace moves across the screen of the oscilloscope, time is represented. - ✔ ✔ Answer B is correct! An oscilloscope converts electrical signals into a visual image representing voltage chanes over a specific period of time. B is a false statement
All of these statements about halogen headlight bulb replacements are true EXCEPT:
A) handle the halogen bulb only by the base.
B)do not drop or scratch the bulb.
C)change the bulb with the headlights on.
D)keep moisture away from the bulb. - ✔ ✔ Answer C is correct! When replacing a halogen lightbulb always turn off the headlights and allow the bulb to cool. Keep moisture away from the bulb, and handle the bulb by its base. Do not scratch or drop the bulb. Coat the terminals in dielectric grease to minimize corrosion.
All of these statements about rear defoggers are true EXCEPT:
A) many rear defoggers are controlled by a timer.
B)when the defogger is on, 9.5 volts are supplied to the grid.
C)each track in the grid is parallel to the other tracks.
D) in many defogger circuits, the timer energizes the defogger relay. - ✔ ✔ Answer B is correct! All are true except B, which incorrectly states the amount of voltage supplied to the grid.
All of these statements about remote keyless entry systems are true EXCEPT:
A) on many systems, the interior lights are illuminated when the unlock button on the remote control is pressed.
B)when the interior lights are turned on by the remote keyless entry system, these lights go off after approximately one minute.
C)when interior lights are turned on by the remote keyless entry system, these lights go off when the ignition switch is turned on.
D)the remote control unlocks the doors when the remote transmitter is 100 yars (91 meter) from the vehicle. - ✔ ✔ Answer D is correct! Most remote control units need to be fairly close to activate or deactivate the door locks. 100 yards is quite far away. The other statements are true.
D) a burned solenoid disc and terminals. - ✔ ✔ Answer A is correct! The slower a motor turns, the more amperage it will draw. Therefore the only answer that is correct is A. Worn bushings will cause the motor to turn slower than normal and will cause high current draw.
During an initial display on a digital instrument cluster, some of the segments in the fuel gauge are not illuminated. All the other segments are illuminated properly. To correct this problem:
A) the fuel gauge segments should be replaced.
B)test the fuel gauge circuit from the gauge to the sending unit.
C)replace the digital instrument display.
D)test the instrument voltage limiter. - ✔ ✔ Answer C is correct! The problem stated in this question is that some of the segments of the fuel gauge in a digital instrument cluster are not illuminating. The question asked for the way to fix the problem. Th eonly way to fix the problem of the missing gauge segments is to replace the entire instrument cluster.
The cigar lighter requires repeated fuse replacements. The cause of this problem could be:
A) high resistance in the lighter element.
B)a high resistance connector on the cigar lighter.
C)a shorted lighter element
D) a grounded wire between the lighter and the chassis. - ✔ ✔ Answer C is correct! High resistance always decreases current flow, and low current will never cause a fuse to blow.
The doors on a vehicle won't unlock with the remote keyless entry. These could all be the cause EXCEPT:
A. Bad passenger door lock motor
B. Blown circuit breaker
C. Weak transmitter battery
D. Interference from a stronger radio transmitter - ✔ ✔ Correct answer A - The faulty door lock motor would only prevent that door from opening. It has nothing to do with the operation of the other doors. All of these other options might cause the doors to remain locked.
The horn is making a weak sound. Technician A believes the faulty power connection is the reason. Technician B believes the faulty fuse might be the cause. Who is correct?
A. Technician A
B. Technician B
C. Both technicians
D. Neither technician - ✔ ✔ Correct answer A - When the horn is weak, the current is too low. Poor electrical connections could be the cause. When the fuse is blown, the horn doesn't sound at all.
The power seat system is noisy when operated. All of these might be the cause EXCEPT:
A. Lack of lubricant
B. Faulty motor
C. Bad ground
D. Faulty transmission - ✔ ✔ Correct answer C - All of these could lead to a noisy operation except for a bad ground. This would make the seat operate slowly or disable it completely. It will not lead to noise.
The rear defogger grid is being tested. Technician A believes that the voltmeter should decrease its reading while probing a grid line as it gets close to the ground bus bar. Technician B believes that when the voltmeter reads 12 volts at both ends of the grid line, it means there's an open in the grid line. Who is correct?
A. Technician A
B. Technician B
C. Both technicians
D. Neither technician - ✔ ✔
Two technicians discuss the state of charge of a battery. Technician A states that a specified gravity of 1.225 at 80F shows the battery has a state of charge at about 75%. Technician B states that it's possible to use the hydrometer to check the state of charge if you are troubleshooting a maintenance-free battery. Who is correct?
A. Technician A
B. Technician B
C. Both technicians
D. Neither technician - ✔ ✔ Correct answer A - Tech A is correct. The reason Tech B is incorrect is that maintenance free batteries don't contain any openings. This means there is nowhere to check the gravity with the hydrometer.
What solder type is needed for instrument panel wiring repair?
A. 60/40 with no flux
B. Acid core
C. 50/50 with acid paste flux
D. Rosin core - ✔ ✔ Correct answer D - Rosin core is the only solder type to ensure integrity in this repair. It's specified for use on any electric repair. The other options would be unacceptable ways to perform the repair.
What tool can check continuity in wires that carry digital signals?
A. Voltmeter
B. Logic probe
C. Analog meter
D. Megger meter - ✔ ✔ Correct answer B - The logic probe is the only tool you could use to measure digital signals. The voltmeter measures electrical potential difference between two points in an electric circuit. An analog meter measures voltage, current, and resistance. The megger meter measures insulation resistance of electrical system
What type of problem is indicated by a lower than normal amperage reading when a circuit is activated?
A ) An open
B) A short
C ) High resistance in the circuit
D) A blown fuse - ✔ ✔ Answer C is correct! Lower amperage is always caused by higher than normal resistance somewhere in the circuit. An open circuit has no current flow and therefore A is not correct. A short would cause higher than normal current flow. A blown fuse is caused by a short, which would not cause lower than normal current flow through the circuit.
What would be the least likely reason you experience a dim headlight out of these options?
A. Low output from the alternator
B. Headlight connector is corroded
C. Headlight wiring has high resistance
D. Broken or damaged headlight assembly - ✔ ✔ Correct answer A - All of these reasons could be the cause of a dim headlight but A is the least likely. More common symptoms of a failing alternator are a dead battery, engine stalling, odd noises and the service engine light
When a faulty fuel gauge indicates a full tank, what's the most likely reason?
A. Stuck float in the up position
B. Open fuse
C. Broken gauge
D. Wire leading to sending unit ground - ✔ ✔ Correct answer D - While there could be many causes; this is the most likely as the question indicated. It can also cause other symptoms such as erratic readings and stuck on empty as well. The least common cause would be trouble with the instrument panel itself.
Which of the following is the LEAST likely cause for an inoperative retractable headlight door?
A)A defective headlight motor
B) Loose or broken vacuum lines
C)A poor headlamp ground
D)A faulty limit switch - ✔ ✔ Answer C is correct! The least likely cause of the problem is a poor headlight ground. This problem would affect the brilliance of the headlight, not the performance of the retractable door. The other answers or statements are correct.
Which of the following is the LEAST likely cause for an inoperative windshield washer system, if the windshield wipers work properly?
A)Low fluid levels
B) Defective switch
C)Defective pump
D)Blown fuse - ✔ ✔ Answer D is correct! Because the windshield wipers function normally, you can assume that the fuse for the circuit is okay. It is unlikely that the vehicle will have a separate fuse for the washer system; therefore D is not a likely cause of the problem.
Which of these is true about a series circuit?
A. Lowest resistance contains the most current
B. Lowest resistance contains the highest voltage drop
C. Highest resistance contains the highest voltage drop
D. Highest resistance contains the most current - ✔ ✔ Correct answer C - According to Kirchhoff's Voltage Law: Voltage higher before resistance than after, which is the result of total applied voltage not equal at both ends of a single load circuit. The resistance opposes electron flow which results in voltage loss applied to the load. This loss is voltage drop with the voltage consumed as current travels through resistance. If you have higher resistance, you have higher drop.
While discussing an alternator that has zero output, Technician A states that the field circuit might have an open circuit. Technician B states that the fusible link might be open to the alternator from the battery. Who is correct?
A. Technician A
B. Technician B
C. Both technicians
D. Neither technician - ✔ ✔ Correct answer C - Both techs are correct. It's possible that the field circuit might have an open circuit. It's also true that it could be an open fusible link from the battery to the alternator.
While performing a starter current draw test, you notice the current draw is more than specified. The battery voltages and cranking speed appear to be less than specified. What is the cause of your problem?
A. High resistance in the field windings
B. A burned solenoid disc and terminals
C. Worn bushings in the starter motor
D. High resistance in the battery positive cable - ✔ ✔ Correct answer C - Both techs are correct. Worn bushes commonly cause a high current draw in the starter circuit. They lead to binding and turning resistance. You also would use the ammeter to check current draw and amperage.
While you use a DMM voltmeter function to evaluate voltage drop, the meter leads need to be connected in what way?
d. Highest resistance has highest voltage drop - ✔ ✔
- When a Digital Multimeter (DMM) is used to measure DC voltage and is connected in parallel to the load device, which of the following defines the reading?
a. Amperage reading
b. Voltage drop
c. Voltage spike
d. Pulse width modulation - ✔ ✔
- Which of the following tools can be used to check the continuity of wires that carry digital signals?
a. Megger Meter
b. Analog meter
c. Logic probe
d. Voltmeter - ✔ ✔
- Using a DMM (Digital Multimeter), a fully charged 12 volt battery should indicate how much voltage on the open circuit voltage (OCV) test?
a. 9.6 volts
b. 4 volts per cell
c. 1 volt per cell
d. 12.6 volts - ✔ ✔
- Two technicians are discussing a battery's state of charge. Technician A says a specific gravity of 1. at 80F indicates that a battery's state of charge is approximately 75%. Technician B says you can use a hydrometer to check battery state of charge on a maintenance free battery. Who is right?
a. A only
b. B only
c. Both A and B
d. Neither A nor B - ✔ ✔
