Question 1

What is a possible disadvantage of using wireless ESTs to reprogram PCMs?
A) Wireless data transmission is extremely slow.
B) Wireless data transmission is not secure.
C) They interfere with commercial and residential wifi systems.
D) The wireless data transfer is not 100% stable.

Accepted Answer

The wireless data transfer may not be stable due to interference or other factors, leading to potential errors or failures in reprogramming the PCM.

Question 2

What condition will result from a plugged oil cooler?
A) High oil temperatures.
B) Low oil temperatures.
C) Immediate engine seizure.
D) Complete blockage of oil flow in the engine.

Accepted Answer

When the oil cooler is plugged, it restricts the flow of oil and causes the oil temperature to rise. This can lead to engine overheating and potential damage if not addressed. Low oil temperatures or immediate engine seizure are not typically associated with a plugged oil cooler, and complete blockage of oil flow is unlikely as there are usually other ways for oil to reach the engine even if the cooler is blocked.

Question 3

How do you load test the resistance of a modules power circuit?
A) Connect an equivalent load via the module connection stub and measure voltage drop.
B) Use a breakout box and measure voltage drop when the module is powered.
C) Connect a DMM in series with the ground circuit and measure the voltage drop.
D) Measure the resistance across the modules power and ground pins.

Accepted Answer

Load testing involves applying an equivalent load to the circuit and measuring the voltage drop to assess the circuit's ability to handle the load, which is described in option A.

Question 4

A diesel engine produces pronounced combustion knock along with white smoke emission. Which of the following is the more likely cause?
A) High sulfur fuel.
B) Advanced fuel injection timing.
C) Out of balance fuel injection system.
D) Air leak in suction side of the fuel subsytem system.

Accepted Answer

The answer of A diesel engine produces pronounced combustion knock...

Question 5

When a EST fails to validate a handshake with a module what is the first step the technician should perform?
A) Check the functionality of the EST and the connection cables.
B) Reboot the PCM and attempt the handshake again.
C) Start a databus diagnostic routine.
D) Remove the module and diagnose.

Accepted Answer

The first step the technician should perform when an EST fails to validate a handshake with a module is to check the functionality of the EST and connection cables. This will ensure that the problem is not caused by a hardware issue. Rebooting the PCM or removing the module should only be done if the issue persists after checking the functionality of the EST and connection cables. Starting a databus diagnostic routine may also be necessary depending on the results of the functionality check.

Question 6

What does the term electronic service tool (EST) refer to?
A) Traditional tools that have electronic readouts e.g. digital torque wrench.
B) Dash installed digital displays.
C) A range of electronic service instruments.
D) An amp volt resistance tester.

Accepted Answer

The term electronic service tool (EST) refers to a range of electronic service instruments used in the automotive industry, including diagnostic equipment, programming tools, and software applications. A and B refer to specific types of tools or displays, while D is a specific instrument and not part of the EST category.

Question 7

When diagnosing a data bus with a communication failure on all modules, voltage fluctuations exceeding 5 volts DC indicate what condition?
A) Partially open grounds.
B) Stray voltage spikes generated by acidic engine coolant .
C) Electromagnetic or radio frequency interference.
D) Defective V-ref circuit.

Accepted Answer

Electromagnetic or radio frequency interference can cause voltage fluctuations exceeding 5 volts DC on a data bus with communication failure on all modules.

Question 8

Why should a DMM be used for circuit testing instead of older analog meters?
A) A DMM is more accurate.
B) Analog meters can damage solid-state components.
C) DMM have many more useful features.
D) Analog meters are more difficult to read.

Accepted Answer

The answer of Why should a DMM be used for...

Question 9

What is a SIS?
A) Manual revisions available from the manufacturers website.
B) Online training system use by several manufacturers.
C) Manufacturer's internet based service information system.
D) Sensor In Sensor technology that simplifies engine electronics.

Accepted Answer

SIS stands for Service Information System, which is an internet-based system provided by manufacturers that contains service and repair information for their products.

Question 10

What are the two categories of diagnostic trouble codes?
A) Engine and chassis.
B) Binary and analog.
C) Long and short.
D) Active and historic.

Accepted Answer

The two categories of diagnostic trouble codes are active and historic. Active codes indicate that there is currently an issue with the vehicle, while historic codes indicate that there was a past issue that has been resolved. The other answer choices do not accurately represent the categories of diagnostic trouble codes.

Question 11

What does blue smoke in the exhaust usually indicate?
A) Ignition misfires.
B) DPF failure.
C) Air in the high pressure fuel circuit.
D) Lube oil in the combustion process.

Accepted Answer

Blue smoke in the exhaust usually indicates that there is lube oil in the combustion process, which can be caused by worn valve guides, piston rings or cylinder walls.

Question 12

What condition is indicated by transient high exhaust temperatures or a visible glow from the DPF canister at night?
A) Low DEF level.
B) Inlet air restrictions.
C) High altitude operation.
D) Normal operating condition in a vehicle equipped with a DPF during regeneration.

Accepted Answer

Transient high exhaust temperatures or a visible glow from the DPF canister at night indicates a normal operating condition in a vehicle equipped with a DPF during regeneration. During regeneration, the temperature in the DPF increases to burn off accumulated particulate matter. This process can cause the DPF to glow or create high exhaust temperatures. It is not indicative of low DEF level, inlet air restrictions, or high altitude operation.

Question 13

What adapter is required to connect to the chassis data bus on a light duty vehicle?
A) J1962 data link adapter.
B) Serial connector.
C) RS232 connector.
D) USB 2.0 connector.

Accepted Answer

The J1962 data link adapter is a standard OBD-II connector that is used to access the chassis data bus on most light duty vehicles. It is required for diagnostic and programming tasks on the vehicle's onboard computer system. Serial connector, RS232 connector, and USB 2.0 connector are not commonly used to connect to the data bus on light duty vehicles.

Question 14

Which of the following is a function of a cylinder balance test?
A) Test the weight of individual pistons.
B) Dynamically test cylinder fueling balance.
C) To determine if individual cylinders are the cause of engine vibrations.
D) To make sure cylinder walls are wearing at the same rate.

Accepted Answer

A cylinder balance test is used to dynamically test the fueling balance of each cylinder to ensure they are contributing equally to the engine's power output.

Question 15

How do you test a inductive pulse generator sensor?
A) Measure the resistance across the sensors terminals.
B) Set a DMM to AC volts and test the output by spinning the sensors wheel.
C) There is now way to test these sensors simply replace them.
D) Load test the sensor with 5V DC.

Accepted Answer

The best way to test an inductive pulse generator sensor is to set a DMM to AC volts and test the output by spinning the sensor's wheel. This will give an accurate reading of the sensor's output and allow for any potential issues to be identified. The other options listed are not effective methods for testing this type of sensor.

Question 16

After repairing a faulty EGR circuit which caused black smoke exhaust on a 2008 Ford diesel pickup, technician replaces the DPF. Technician B removes, cleans our accumulated ash and reinstalls the DPF. Which technician used the correct procedure?
A) Technician A only.
B) Technician B only.
C) Both A and B.
D) Neither A nor B.

Accepted Answer

The answer of After repairing a faulty EGR circuit which...

Question 17

What is the purpose of diagnostic spoons?
A) To provide DMM probe contacts points while protecting pins and sockets.
B) Provide a quick method to short out multiple pins.
C) A tool to remove pins from connectors.
D) Provide high impedance scope probe contacts.

Accepted Answer

Diagnostic spoons are used to provide DMM probe contact points while protecting pins and sockets. They are designed to fit into the sockets of various connectors to provide a safe and secure connection for testing purposes. They protect the pins and sockets from damage while allowing for a reliable and accurate connection for diagnostic testing.

Question 18

What is a common device used with DMMs to access active electrical circuits without compromising functionality?
A) Needle probe.
B) High impedance probe.
C) Breakout box.
D) Alligator clips.

Accepted Answer

A breakout box is commonly used with Digital Multimeters (DMMs) to access active electrical circuits without compromising their functionality. It allows for the measurement of electrical signals without disrupting the circuit's operation.

Question 19

A resistor with a black third stripe (decimal multiplier) should have what resistance value?
A) 1000 ohms or less.
B) Over 100 ohms but less than 1000 ohms.
C) Over 1000 ohms.
D) Less than 100 ohms.

Accepted Answer

The third stripe on a resistor indicates the multiplier. A black stripe in this position means a multiplier of 1, so the resistance value would be less than 100 ohms, assuming the first two stripes represent a value less than 10.

Question 20

Technician A troubleshoots vehicle electrical issues by testing the most likely suspect component based on experience. Technician B strictly follows the manufacturers recommended diagnostic testing routine. Who is correct?
A) Technician A only.
B) Technician B only.
C) Both A and B.
D) Neither A nor B.

Accepted Answer

Technician B is more likely to correctly diagnose the issue by following the manufacturer's recommended diagnostic testing routine, which is based on the specific design and components of the vehicle. Technician A's approach of relying solely on their experience may lead to misdiagnosis and unnecessary repairs.

Quiz 15: Diagnostics and Testing

What is a possible disadvantage of using wireless ESTs to reprogram PCMs?

What condition will result from a plugged oil cooler?

How do you load test the resistance of a modules power circuit?

A diesel engine produces pronounced combustion knock along with white smoke emission. Which of the following is the more likely cause?

When a EST fails to validate a handshake with a module what is the first step the technician should perform?

What does the term electronic service tool (EST) refer to?

When diagnosing a data bus with a communication failure on all modules, voltage fluctuations exceeding 5 volts DC indicate what condition?

Why should a DMM be used for circuit testing instead of older analog meters?

What is a SIS?

What are the two categories of diagnostic trouble codes?

What does blue smoke in the exhaust usually indicate?

What condition is indicated by transient high exhaust temperatures or a visible glow from the DPF canister at night?

What adapter is required to connect to the chassis data bus on a light duty vehicle?

Which of the following is a function of a cylinder balance test?

How do you test a inductive pulse generator sensor?

After repairing a faulty EGR circuit which caused black smoke exhaust on a 2008 Ford diesel pickup, technician replaces the DPF. Technician B removes, cleans our accumulated ash and reinstalls the DPF. Which technician used the correct procedure?

What is the purpose of diagnostic spoons?

What is a common device used with DMMs to access active electrical circuits without compromising functionality?

A resistor with a black third stripe (decimal multiplier) should have what resistance value?

Technician A troubleshoots vehicle electrical issues by testing the most likely suspect component based on experience. Technician B strictly follows the manufacturers recommended diagnostic testing routine. Who is correct?