Deck 15: Diagnostics and Testing

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.

Answer 1

D

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.

Answer 2

A

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.

Answer 3

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.