ASE Practice Test (A6: Electrical/Electronic Systems) 1 — Questions and Answers

Question 1: To check the continuity of wires that carry digital signals, which of the following tools can be used?

Voltmeter
Megger meter
Analog meter
Logic probe (Correct answer)

Correct answer: Logic probe

A logic probe is specifically designed to detect and display the presence of digital signals (high, low, or pulsing states) in electronic circuits without significantly loading the circuit. While a voltmeter can measure voltage, it is less effective for quickly interpreting the dynamic states or fast pulses characteristic of digital signals. A megger meter measures insulation resistance, and an analog meter is less precise for digital signals.

Question 2: When using the passenger side control switch, the passenger side power window works properly, but when using the driver's side master control switch, the window only works in the DOWN position. Which of these possibly be the source of the problem?

A grounded power wire to the power window circuit breaker
An open circuit in the driver’s side master control switch (Correct answer)
A pinched wire from the passenger side control switch to the window motor
An open wire to the driver’s side window motor

Correct answer: An open circuit in the driver’s side master control switch

If the passenger window works correctly from its own switch but only works in the DOWN position from the driver's master control switch, it indicates an issue within the master switch itself. Specifically, the 'UP' contact or circuit for the passenger window within the driver's master switch is likely open or faulty, preventing the 'UP' signal from being sent. The passenger switch's full functionality confirms the motor and associated wiring are otherwise fine.

Question 3: Which of the following statements regarding a series circuit is correct?

Highest resistance contains the highest voltage drop (Correct answer)
Highest resistance contains the most current
Lowest resistance contains the most current
Lowest resistance contains the highest voltage drop

Correct answer: Highest resistance contains the highest voltage drop

In a series circuit, the current flowing through all components is the same. According to Ohm's Law (V=IR), the voltage drop across a component is directly proportional to its resistance. Therefore, the component with the highest resistance in a series circuit will experience the largest voltage drop across it.

Question 4: A fully charged 12 volt battery should indicate how much voltage on the open circuit voltage (OCV) test when using a DMM (Digital Multimeter).

4 volts per cell
1 volt per cell
12.6 volts (Correct answer)
9.6 volts

Correct answer: 12.6 volts

A fully charged 12-volt lead-acid battery consists of six individual cells, with each cell producing approximately 2.1 volts when fully charged. Therefore, a fully charged 12-volt battery should indicate around 12.6 volts (6 cells x 2.1 V/cell) when measured with a Digital Multimeter (DMM) during an open-circuit voltage (OCV) test.

Question 5: Technician X says that if a fusible link in the alternator charging circuit is replaced with system sized wire, the circuit will be unprotected. Technician Y says that if a fusible link in the alternator charging circuit is replaced with system sized wire, the battery will overcharge. Who is right?

Both X and Y
Neither X nor Y
X only (Correct answer)
Y only

Correct answer: X only

A fusible link is a safety device designed to melt and open a circuit when excessive current flows, protecting other components. If a fusible link is replaced with a standard wire of the same gauge, it loses its protective function. This 'system sized wire' will not melt under overcurrent conditions, leaving the circuit unprotected and vulnerable to damage from excessive current. Technician Y's statement about overcharging is incorrect, as fusible links are for overcurrent protection, not voltage regulation.

Question 6: When using a DMM voltmeter function to evaluate voltage drop, how should the meter leads be connected?

On the positive side of the circuit
To non-conductive material
Across the circuit or component (Correct answer)
In series with the circuit

Correct answer: Across the circuit or component

To accurately measure voltage drop across a circuit or a specific component, the DMM voltmeter leads must be connected in parallel, or 'across,' the points where the voltage difference is to be measured. This allows the meter to read the potential difference between those two points, indicating how much voltage is being consumed or 'dropped' by that part of the circuit. Connecting in series would measure current, not voltage drop.

Question 7: Two technicians are discussing a battery's state of charge. Technician X says a specific gravity of 1.225 at 80F indicates that a battery's state of charge is approximately 75%. Technician Y says you can use a hydrometer to check battery state of charge on a maintenance free battery. Who is right?

Both X and Y
Neither X nor Y
X only (Correct answer)
Y only

Correct answer: X only

Correct answer: X only Technician X is correct and Technician Y is wrong because maintenance free batteries do not have openings to check the specific gravity of the electrolyte with a hydrometer.

Question 8: A starter solenoid clicks but the starter does not crank the engine. Technician X says that burned solenoid contacts could be the cause. Technician Y says that a poor battery cable connection could be the cause. Who is right?

Both X and Y (Correct answer)
Neither X nor Y
X only
Y only

Correct answer: Both X and Y

Correct answer: Both X and Y Both technicians are correct.

Question 9: When linked to both sides of the rotor, an analog ohmmeter needle will not move. What does the rotor winding indicate?

It is shorted
It is complete
It is grounded
It is open (Correct answer)

Correct answer: It is open

Correct answer: It is open This ohmmeter is showing infinite resistance or infinity. This is what happens when the needle doesn’t move. With the rotor winding shows, the circuit is open.

Question 10: When a technician performs a load test on a battery, the battery voltage falls below specifications. Which of the following actions is the MOST LIKELY to be taken?

Replace the voltage regulator
Replace the battery (Correct answer)
Recharge the battery and retest it
Recharge the battery and return it to service

Correct answer: Replace the battery

Correct answer: Replace the battery The battery was tested under load and failed.

Question 11: The following could cause high starter current draw, EXCEPT:

a seized A/C compressor
worn starter bushings
a failed starter relay (Correct answer)
grounded field coils

Correct answer: a failed starter relay

Correct answer: a failed starter relay A failed starter relay could not be the cause of high starter current draw.

Question 12: Technician X states that a short circuit to ground in a circuit decreases resistance. Technician Y states that a short circuit increases current flow. Who is correct?

Both technicians (Correct answer)
Neither technician
Technician X
Technician Y

Correct answer: Both technicians

Correct answer: Both technicians 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.

Question 13: Two technicians are discussing testing a battery using an electronic conductance or continuity tester. Technician X says some of these testers can load test a battery. Technician Y says you need to make sure that the ignition switch and all accessories are off. Who is right?

Both X and Y
Neither X nor Y
X only
Y only (Correct answer)

Correct answer: Y only

Correct answer: Y only Technician X is wrong because this device cannot apply a load. It checks battery conductance.

Question 14: On an automatic transmission vehicle, the starter does not crank and the solenoid does not click. Any of these could be the source of the problem. EXCEPT

an open in the solenoid ground circuit
a misadjusted neutral safety switch
an open solenoid hold-in winding (Correct answer)
an open circuit between the solenoid and the ignition switch

Correct answer: an open solenoid hold-in winding

Correct answer: an open solenoid hold-in winding An open solenoid hold-in winding could not be the cause of the problem.

Question 15: You discover the current draw is higher than specified while performing a starter current draw test. The battery voltages and cranking speed appear to be lower than the manufacturer's specifications. What's the source of your issue?

Worn bushings in the starter motor (Correct answer)
High resistance in the battery positive cable
High resistance in the field windings
A burned solenoid disc and terminals

Correct answer: Worn bushings in the starter motor

Correct answer: Worn bushings in the starter motor As the motor turns slower, it draws more amperage. Worn bushings cause the motor to turn slower than it should. This leads to a high current draw.

Question 16: Two technicians are discussing an alternator with zero output. Technician X says the field circuit may have an open circuit. Technician Y says the fusible link may be open from the battery to the alternator. Who is right?

Both X and Y (Correct answer)
Neither X nor Y
X only
Y only

Correct answer: Both X and Y

Correct answer: Both X and Y Both statements are correct.

Question 17: The oil pressure light stays on whenever the engine is running. The oil pressure has been checked and is at specification. Technician X says that a ground in the circuit between the indicator light and the pressure switch could be the cause. Technician Y says that an open in the pressure switch could be the cause. Who is right?

Both X and Y
Neither X nor Y
X only (Correct answer)
Y only

Correct answer: X only

Correct answer: X only Technician X is correct. A ground in the circuit between the indicator light and the pressure switch could be the cause why the oil pressure light stays on whenever the engine is running.

Question 18: Technician X states that a loose serpentine alternative drive belt might lead to overcharging. Technician Y states that undersized wiring between the battery and alternator might cause undercharging. Who is correct?

Both technicians
Neither technician
Technician X
Technician Y (Correct answer)

Correct answer: Technician Y

Correct answer: Technician Y Tech X is incorrect because undercharging is the result of a slipping belt. Tech Y is right because the undersize wiring leads to undercharging. This is caused by higher resistance.

Question 19: A low-output alternator is being full-fielded to determine the cause. Which of the following is the LEAST likely result of full-fielding the alternator?

Low battery voltage level (Correct answer)
High alternator amperage output
High battery voltage level
Battery gassing

Correct answer: Low battery voltage level

Correct answer: Low battery voltage level Full fielding removes the regulator from controlling field current allowing the alternator to go to full output and is unlikely to produce a low battery voltage. This action normally produces high current and voltage. P (Power) = I (Current) x E (Voltage) and is least likely to occur.

Question 20: With the engine running and based in the charging system shown. What will be the digital multimeter (DMM) will display?

regulator operating voltage
charging circuit voltage drop (Correct answer)
ignition switch voltage drop
charging output voltage

Correct answer: charging circuit voltage drop

Correct answer: charging circuit voltage drop In the charging system shown, the digital multimeter (DMM) will display the charging circuit voltage drop.

Question 21: Out of these options, what is the least likely cause of a dim headlight?

Broken or damaged headlight assembly
Headlight wiring has high resistance
Headlight connector is corroded
Low output from the alternator (Correct answer)

Correct answer: Low output from the alternator

Correct answer: Low output from the alternator All of these reasons could be the cause of a dim headlight but D is the least likely. More common symptoms of a failing alternator are a dead battery, engine stalling, odd noises and the service engine light.

Question 22: Technician X says high-intensity discharge (HID) headlights are generally brighter and have a blue tint. Technician Y says a defective turn signal bulb on one side can cause the turn signal on that side not to blink. Who is right?

Both X and Y (Correct answer)
Neither X nor Y
X only
Y only

Correct answer: Both X and Y

Correct answer: Both X and Y Both statements are correct.

Question 23: In the circuit shown, the bulb does not light. To determine the actual voltage at the bulb, the technician should touch the positive probe of the voltmeter to:

ground and the negative probe to point X
ground and the negative probe to point W
point W and the negative probe to ground
point X and the negative probe to ground (Correct answer)

Correct answer: point X and the negative probe to ground

Correct answer: point X and the negative probe to ground To find the actual voltage at the bulb, the technician should touch the positive probe of the voltmeter to point X and the negative probe to ground.

Question 24: The vehicle turn signals begin to flash too slow. Technician X believes that the issue is caused by a faulty flasher. Technician Y believes the bulb is an incorrect type. Who is correct?

Both technicians (Correct answer)
Neither technician
Technician X
Technician Y

Correct answer: Both technicians

Correct answer: Both technicians Both techs are correct. The incorrect wattage and improperly rated flasher could cause the signal to flash incorrectly. Turn on the signal and inspect it to determine the problem.

Question 25: Technician X says you aim HID (High Intensity Discharge) headlights on a level floor with an unloaded vehicle. Technician Y says when aiming any headlights, you must follow the state inspection specifications. Who is right?

Both X and Y (Correct answer)
Neither X nor Y
X only
Y only

Correct answer: Both X and Y

Correct answer: Both X and Y Both statements are correct.

Question 26: The horns in the circuit shown operate only when a jumper wire is connected between terminals 30 and 87 of the horn relay. Technician X says that a failed horn relay could be the cause. Technician Y says that a short-to-ground in the circuit between the horn relay and the horn switch could be the cause. Who is right?

Both X and Y
Neither X nor Y
X only (Correct answer)
Y only

Correct answer: X only

Correct answer: X only Technician X is right. As shown in the circuit, a failed horn relay could be the cause.

Question 27: For instrument panel wiring repairs, what solder type is needed?

Rosin core (Correct answer)
60/40 with no flux
Acid core
50/50 with acid paste flux

Correct answer: Rosin core

Correct answer: Rosin core 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.

Question 28: Technician X says an aiming screen will work on any headlight design to aim the headlights. Technician Y says mechanical aimers are used on HID (High Intensity Discharge) headlights. Who is right?

Both X and Y
Neither X nor Y
X only (Correct answer)
Y only

Correct answer: X only

Correct answer: X only Technician X is correct because the aiming screen is the tool of choice due to the many different headlight designs used. Technician Y is wrong because mechanical aimers are no longer used and were never used on HID headlights.

Question 29: What is the most likely reason of a faulty fuel gauge indicating a full tank?

Open fuse
Broken gauge
Wire leading to sending unit ground (Correct answer)
Stuck float in the up position

Correct answer: Wire leading to sending unit ground

Correct answer: Wire leading to sending unit ground 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. A wire to the sending unit being grounded is the most likely cause on most systems.

Question 30: In instrument lighting, which of the following describes the MOST common type of electrical wiring used?

Copper stranded type (Correct answer)
Aluminum stranded type
Solid copper type
Twisted pair type

Correct answer: Copper stranded type

Correct answer: Copper stranded type Copper stranded type electrical wiring is the correct answer because the other types are not common.

ASE Practice Test (A6: Electrical/Electronic Systems) 1

To check the continuity of wires that carry digital signals, which of the following tools can be used?