ASE A Series Exam Questions

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181.

Technician A says the Body Control Module (BCM) may store a DTC if there's a fault with the electronic instrument cluster. Technician B says the electronic instrument cluster can't perform a self-diagnostic check. Who is correct?

  • Technician A

  • Technician B

  • Both A and B

  • Neither A nor B

Correct answer: Technician A

Technician A is correct. The Body Control Module (BCM) is capable of storing DTCs in some vehicles when there's a fault with the electronic instrument cluster. Sometimes, this fault is also shown on the instrument panel's digital display.

Technician B is incorrect. Some electronic instrument clusters have the capability of performing self checks and alerting when there's a fault. 

182.

Technician A says worn valve guides will cause a vacuum gauge reading that has a drifting needle. Technician B says excessive back pressure in the system can be seen on a vacuum gauge reading showing a vibrating needle at idle that steadies out once engine speed increases.

Who is correct?

  • Neither A nor B

  • Technician A

  • Technician B

  • Both A and B

Correct answer: Neither A nor B

Both technicians are incorrect. Worn valve guides present on a vacuum gauge reading with a vibrating needle at idle that steadies out with increased engine speed. If the vacuum gauge has a drifting needle, the cause is most likely a minor intake leak at the manifold or bad fuel injector O-rings.

If there's excessive back pressure in the system, the gauge shows a gradual drop at idle and a decreased reading with rpm. 

183.

Generally, total camshaft runout should not exceed:

  • 0.002"

  • 0.001"

  • 0.005"

  • 0.006"

Correct answer: 0.002"

Runout is the distance the camshaft wobbles out of its axis of rotation. It is checked by placing the camshaft in V-blocks and measuring with a dial indicator. Camshaft runout over 0.002" is considered excessive, requiring replacement of the camshaft.

184.

What happens to the current flow when voltage goes down and resistance stays the same?

  • Goes down

  • Goes up

  • Stays the same

  • Open circuit is created

Correct answer: Goes down

If the voltage goes down, but the resistance in a circuit remains the same, the current flow will also go down accordingly. The same is true when the voltage goes up, with the current flow also going up as long as the resistance remains the same.

However, when the resistance goes up, current goes down as long as the voltage remains the same. 

185.

Technician A says brake fluid should last the life of the vehicle. Technician B says brake fluid absorbs moisture from the air.

Who is correct?

  • Technician B

  • Technician A

  • Both A and B

  • Neither A nor B

Correct answer: Technician B

Only technician B is correct. Brake fluid absorbs moisture from the air. Because of this, brake fluid should be changed on a regular basis to prevent corrosion and deterioration of the hydraulic system components.

186.

All of the following statements about an AC generator are true EXCEPT:

  • Produce less output at lower RPMs than DC generators

  • Can spin faster than DC generators without self-destruction

  • Small than DC generators

  • Lighter than DC generators 

Correct answer: Produce less output at lower RPMs than DC generators

The AC generator produces more output at lower RPMs than the DC generators. They can also spin faster than the DC generators without self-destruction.

AC generators are known for being smaller and lighter than the standard DC generator. 

187.

A technician is using a scan tool to check shift solenoid operation. While monitoring the live data, it is noted that the TCM commands the solenoid on but nothing happens.

Which of the following is the least likely cause?

  • Faulty TCM

  • Worn band

  • Faulty solenoid

  • Problem in the solenoid wiring

Correct answer: Faulty TCM

The TCM is unlikely to be the problem, since it can be observed commanding the solenoid on. The lack of response from the solenoid and corresponding hydraulics indicates a problem with the hydraulics (clutch, band, etc.), the solenoid, or the solenoid wiring.

188.

All of the following are part of the primary ignition system EXCEPT:

  • Spark plugs

  • Ignition switch

  • Pickup coil

  • Battery

Correct answer: Spark plugs

The ignition system is divided into two parts: the primary, low-voltage side and the secondary, high-voltage side. The primary side includes the battery, ignition switch, primary winding of the coil, and pickup coil (where applicable). The coil is a transformer that converts low voltage into the high voltage needed to fire the spark plugs. 

The secondary side of the ignition circuit includes the coil secondary windings, distributor cap, and rotor (where applicable), as well as the spark plugs and wires.

189.

Bearing preload is usually measured with what?

  • Torque wrench 

  • Dial indicator 

  • Feeler gauge 

  • Micrometer 

Correct answer: Torque wrench

Preload should be checked during reassembly of a transmission that uses roller bearings. Preload puts a slight drag on a shaft as it is rotated, and is measured using a torque wrench or spring scale. 

190.

Two technicians are considering retrofitting an R-12 AC system to R-134a. Technician A says R-134a can leak out easier than R-12 refrigerant. Technician B says you need less R-134a than R-12 to achieve the desired pressure.

Who is correct?

  • Both A and B

  • Technician A 

  • Technician B

  • Neither A nor B

Correct answer: Both A and B

R-134a tetrafluoroethane is made up of smaller molecules than R-12 dichlorodifluoromethane. Because of this, it leaks out easier.

When retrofitting an R-12 AC system to R-134, about 5% less refrigerant, by weight, is required to achieve the desired pressure differentials for comparable cooling to the old R-12.

191.

Technician A says the torsion dampener is used to cancel out engine firing pulses being transmitted to the transmission. Technician B says a wave or cushion spring is used to help absorb the initial shock of clutch engagement.

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. The center of the clutch hub has torsional dampeners that absorb the initial shock of clutch engagement and dampen the engine firing pulses. The wave spring or cushion spring is between the clutch disc friction surfaces. It helps absorb the initial shock of engagement and allows for smooth clutch operation.

192.

Technician A says a one-way roller clutch consists of a hub, rollers, and springs that fit inside a drum. Technician B says a one-way roller clutch uses sprags to lock and unlock the clutch.

Who is correct?

  • Technician A

  • Technician B

  • Both A and B

  • Neither A nor B

Correct answer: Technician A

Only technician A is correct; a one-way roller clutch consists of a hub, rollers, and springs that fit inside a drum. In this design, the rollers wedge themselves against the cams in response to the rotation of the hub, locking the clutch in one direction.

Technician B is incorrect because it is a one-way sprag clutch, not a one-way roller clutch, that uses sprags to lock and unlock the clutch.

193.

Technician A says when diagnosing an HVAC problem you should first check for diagnostic trouble codes (DTCs). Technician B says you should first check for technical service bulletins (TSBs).

Who is correct?

  • Neither A nor B

  • Technician A

  • Technician B

  • Both A and B

Correct answer: Neither A nor B

Both technicians are incorrect. When diagnosing an HVAC problem, you should first verify the customer complaint. Only then should you proceed to other diagnostic steps such as checking for DTCs and TSBs.

194.

Which type of system relies on oil pressure for injector operation?

  • HEUI

  • Common rail 

  • Distributor injection pump 

  • PLN

Correct answer: HEUI

Some Ford/Navistar diesel engines use a system called hydraulic electronic unit injection (HEUI). In this system, the injectors are hydraulically actuated by engine oil pressure from a high-pressure oil pump, then fired by the PCM.

195.

What type of actuator always uses a potentiometer?

  • Variable-position 

  • Three-position 

  • Dual-position

  • Single-position 

Correct answer: Variable-position

A variable-position actuator can move to any position in its range. All variable-position actuators use a feedback sensor, or potentiometer, to detect actual position.

196.

Technician A says rotor runout should be measured with a micrometer. Technician B says rotor parallelism should be measured with a dial indicator.

Who is correct?

  • Neither A nor B

  • Technician A

  • Technician B

  • Both A and B

Correct answer: Neither A nor B

Both technicians are incorrect. Runout is the side-to-side wobble of the rotor as it turns, which is measured with a dial indicator. Parallelism is the variation in thickness, measured with a micrometer.

197.

A vehicle exhibits noisy cranking. All of the following are possible causes EXCEPT:

  • Bad solenoid

  • Damaged pinion gear

  • Incorrect pinion depth

  • Faulty flywheel ring gear

Correct answer: Bad solenoid

Noisy cranking can be caused by a damaged pinion gear, incorrect pinion depth or a faulty flywheel ring gear. Other causes include starter-to-engine block shimming, when applicable. 

A bad solenoid won't lead to noisy starting. Instead, it will prevent the starter from operating. 

198.

Technician A says if the vehicle does not move in drive or reverse, the problem is likely electrical or hydraulic. Technician B says if the vehicle moves but does not shift correctly, the problem is likely mechanical.

Who is correct?

  • Neither A nor B

  • Technician A

  • Technician B

  • Both A and B

Correct answer: Neither A nor B

Both technicians are incorrect. If the vehicle does not move in drive or reverse, the problem is likely mechanical. If the vehicle moves but does not shift properly, the problem is likely electrical or hydraulic. If the vehicle is able to move backward and forward, most major mechanical components are functioning. Of course, further diagnosis would be needed to determine the actual fault.

199.

While lifting the EGR valve diaphragm up while the engine is idling, the idle speed doesn't change.

What does this indicate?

  • Clogged EGR passages

  • A stuck-open EGR valve 

  • A stuck-closed EGR valve 

  • Proper EGR valve operation 

Correct answer: Clogged EGR passages

EGR passages become clogged with carbon. If there's no change to idle speed while lifting the EGR valve diaphragm, this is the most likely cause. The valve needs to be removed, so the EGR passages can be cleaned. 

200.

Technician A says a 1350 U-joint transmits more torque than a 1100 series U-joint. Technician B says a U-joint with a 15/16" cap transmits more torque than a U-joint with a 1 3/8" cap.

Who is correct?

  • Technician A

  • Technician B

  • Both A and B

  • Neither A nor B

Correct answer: Technician A

Only technician A is correct. The larger the U-joint, the more torque it can transmit. A higher series number corresponds to a larger U-joint size. Therefore, a higher series number can also transmit more torque. By the same token, cap diameter is a general indicator of torque capacity, with larger caps being fitted to bigger and stronger U-joints.