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Quiz Session - Attempts With Random Questions

ASE T Series Exam Questions

Page 2 of 20

21.

A technician notices low compression in two neighboring cylinders. Which of these is the most likely cause?

  • Cracked block

  • Bad piston rings

  • Inaccurate valve timing

  • Low oil level

Correct answer: Cracked block

A cracked block can cause low compression in neighboring cylinders, as can a blown head gasket or a cracked cylinder head. 

Bad piston rings, inaccurate valve timing, and a low oil level normally lead to low compression in all of the cylinders. 

22.

Technician A says supplemental coolant additives are not needed with wet cylinder liners. Technician B thinks that leaking liner seals may cause coolant in the crankcase and an overheating engine on diesel with wet cylinder liners.

Who is correct?

  • Technician B

  • Technician A

  • Both A and B

  • Neither A nor B

Correct answer: Technician B

Technician A is incorrect because certain supplemental coolant additives (SCAs) are needed to prevent the pitting and wear of wet cylinder liners. 

Technician B is correct because leaking liner seals would lead to overheating and coolant leaking into the crankcase. 

23.

On a seven-pin trailer connector, what does the white wire represent?

  • Ground return to the tow vehicle

  • Tail and license plate lights

  • Auxiliary circuit

  • Clearance lights

Correct answer: Ground return to the tow vehicle

The white wire represents the ground return to the tow vehicle. The tail and license plate lights are connected to the brown wire.

Blue represents the auxiliary circuit, while black is used for the clearance, side marker, and ID lights. 

24.

Technician A says ether should be used to help start diesel engines. Technician B says electronic controlled engines don't inject fuel until engine speed is at least 150 RPM. Who is correct?

  • Technician B

  • Technician A 

  • Both A and B

  • Neither A nor B

Correct answer: Technician B

Only technician B is correct. On modern engines, the onboard electronics will prevent fuel injection until engine speed is at least 150 RPM. Technician A is wrong because ether should never be used to start a diesel engine, because it can cause detonation. 

25.

Which type of switch cycles the compressor on and off in relation to evaporator outlet temperature?

  • Thermostatic cycling 

  • Pressure cycling 

  • Low-pressure cut-out

  • High-pressure cut-out

Correct answer: Thermostatic cycling

Some refrigerant systems use a thermostatic cycling switch to turn the compressor on and off in relation to evaporator outlet temperature. Other systems use a pressure cycling switch to switch the compressor on and off in relation to low-side pressure.

26.

All of the following could cause a manual transmission to overheat except:

  • Restricted transmission cooler lines

  • Low fluid level 

  • Improper gear clearance

  • Bearing failure

Correct answer: Restricted transmission cooler lines

Manual transmissions generally aren't equipped with transmission cooler lines. Coolers are used on automatic transmissions. All of the other options could increase internal transmission friction, resulting in heat buildup.

27.

If alternator voltage rises above 15.0, all the following could be to blame EXCEPT: 

  • Overcharged battery

  • Defective regulator

  • Bad ground connection

  • Shorted components

Correct answer: Overcharged battery

A defective regulator, bad ground connection, and shorted components can all cause the alternator voltage to rise above 15.0, leading to overcharging of the battery.

An overcharged battery is a symptom of high voltage coming from the alternator, not the cause. 

28.

Generally, when performing a cylinder leak down test, leakage should not exceed:

  • 20%

  • 5%

  • 10%

  • 30%

Correct answer: 20%

A cylinder leak down test is used to determine if a cylinder is sealing. This test is performed by introducing compressed air into the cylinder with the piston at top dead center on the compression stroke. Generally, leakage greater than 20% indicates an internal engine problem.

29.

Technician A says a defective push-pull valve causes brake drag. Technician B says the dash-mounted push-pull valve is found in both singular and dual-integrated styles. 

Who is correct?

  • Both A and B

  • Technician A

  • Technician B

  • Neither A nor B

Correct answer: Both A and B

Both technicians are correct. When the push-pull valve is defective, it can lead to premature spring brake application, brake drag, and slow brake release.

Dash-mounted push-pull valves come in two styles: singular and dual-integrated. 

30.

Which of the following is used to ensure antifreeze is within normal operating specs and does not need to be serviced?

  • Refractometer

  • Polarimeter

  • Hydrometer

  • Manometer

Correct answer: Refractometer

A refractometer is used to measure antifreeze concentration and determine whether service is required.

 The polarimeter measures the rotation of polarized light to check the purity of optically active compounds. It has no place in antifreeze inspection. Hydrometers are used to check the battery cells, and manometers are pressure meters.

31.

What is the maximum number of codes an ECU can store?

  • 5

  • 10

  • 15

  • 20

Correct answer: 5

The ECU can store a maximum of 5 codes in memory. When codes are added, the oldest inactive code is dropped from the list. If all the codes are active, they are listed in the order of severity. When there are more than 5 active codes, the least severe one is dropped. 

32.

The pressure protection valve in an air suspension system closes when pressure drops below:

  • 70 psi

  • 50 psi

  • 100 psi

  • 150 psi

Correct answer: 70 psi

The pressure protection valve closes when pressure in an air suspension system drops below 70 psi. This is done to protect the system.

33.

Most speedometers receive their information from which type of sensor?

  • Magnetic pickup

  • Hall effect 

  • Reed switch 

  • Transducer 

Correct answer: Magnetic pickup

Most speedometers and tachometers receive their information from magnetic pickup sensors. These sensors produce a magnetic field near a rotating wheel and generate a voltage signal as the wheel is rotated. 

34.

A meter of at least what impedance should be used when testing low current electronic circuits?

  • 10 megohms

  • 10 ohms 

  • 10 milliohms

  • 10 kilohms 

Correct answer: 10 megohms 

When testing low current flow circuits, it's recommended that a meter of 10 megohms or higher be used, to prevent damage to the circuit and to limit the effect the unit might have on the test's accuracy. 

35.

Generally, what is the maximum allowable current draw on computer-controlled vehicles? 

  • 50 milliamps 

  • 25 milliamps

  • 10 milliamps 

  • 5 milliamps 

Correct answer: 50 milliamps

Most computer-controlled vehicles should draw under 50 milliamps with the key off. Anything more indicates a parasitic drain. 

36.

Technician A says an SAE #1 type circuit breaker trips when open and must be reset manually. Technician B says an SAE #2 type circuit breaker cycles when overloaded. Who is correct?

  • Neither A nor B

  • Technician A

  • Technician B

  • Both A and B

Correct answer: Neither A nor B

Both technicians are wrong. Circuit breakers are circuit protection devices that can be reset, usually automatically. There are two types of circuit breakers used in trucks: SAE #1 and SAE #2. A #2 type circuit breaker trips when open and must be reset manually. An SAE #1 type circuit breaker cycles when overloaded.

37.

All of the following are true regarding hub bearing assemblies except:

  • They can be rebuilt

  • They come with preset clearance 

  • They must be checked for end play

  • The retaining nut torque can be as much as 600 ft-lbs.

Correct answer: They can be rebuilt 

Wheel bearing assemblies come with preset clearances. However, end play must still be checked. Installation involves the technician installing the assembly on the spindle and torquing it to a specified value, sometimes as high as 600 ft-lbs. If the assembly fails, the entire thing must be replaced. 

38.

All of the following conditions should be present when testing an R-134a system except:

  • Temperature control set in the highest position 

  • Blower speed set to high

  • Engine speed at 1,500 RPM or peak governed RPM

  • Recirculation air set

Correct answer: Temperature control set in the highest position 

When testing an A/C system, several conditions must be present, including blower speed set to high, engine speed at 1,500 RPM or peak governed RPM, recirculation air set, and temperature control set to the lowest position. 

39.

The fuse for a power window circuit continually blows. Which of the following is the most likely cause?

  • Binding linkage

  • An open motor circuit 

  • Faulty motor brushes 

  • A poor motor ground

Correct answer: Binding linkage

If the voltage applied to the motor is correct and the circuit continually blows fuses, the linkage is probably binding. 

40.

Technician A says a gauge can be tested by disconnecting it from the sending unit. Technician B says a gauge can be tested using a variable resistor. Who is correct?

  • Both A and B

  • Technician A

  • Technician B

  • Neither A nor B

Correct answer: Both A and B

Both technicians are correct. Disconnecting the gauge from the sending unit should cause the gauge to move to either the top or bottom of the scale. Connecting the gauge to a good ground should then cause the gauge to move to the opposite end of the scale. Some technicians use a variable resistor to move the gauge throughout its range. 

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