Question 1

The OBD II task manager is responsible for ________.
A) controlling the timing of diagnostic tests
B) measuring the coolant temperature
C) calculating spark timing
D) calculating fuel injector timing

Accepted Answer

The OBD II task manager is responsible for controlling the timing of diagnostic tests. It is not responsible for measuring coolant temperature, calculating spark timing, or calculating fuel injector timing.

Question 2

freeze-frame data includes all of the following EXCEPT ________.
A) coolant temperature
B) vehicle speed
C) date of the failure
D) RPM

Accepted Answer

D

Question 3

A vehicle has a flashing MIL when warmed up and driving. What does this mean?
A) Fuel pressure too low
B) Low tailpipe flow
C) Possible catalytic converter damage
D) OBD II self-test complete

Accepted Answer

D

Question 4

A freeze-frame is a ________ of all data at the instant an emission-related DTC is set.
A) comprehensive component monitor
B) snapshot
C) failure record
D) trip

Accepted Answer

A freeze-frame is a snapshot of all data at the instant an emission-related DTC is set. A comprehensive component monitor is a specific type of OBD system test, a failure record is not a term commonly used in OBD diagnostics, and a trip refers to a specific driving cycle.

Question 5

Enable criteria means ________.
A) the same thing as a trip
B) a warm-up cycle
C) conditions for a particular test to be performed
D) a drive cycle

Accepted Answer

Enable criteria refers to the specific conditions that must be met in order for a particular test to be performed. It is not related to a trip, warm-up cycle, or drive cycle.

Question 6

Technician A says that when the MIL is on, the technician should retrieve the DTC and follow the manufacturer's recommended procedure to find the root cause of the problem. Technician B says that all OBD II monitors must have the enable criteria achieved before a test is performed. Who is right?
A) Technician A only
B) Technician B only
C) Both technicians A and B
D) Neither technician A nor B

Accepted Answer

Both technicians A and B are correct. When the MIL (Malfunction Indicator Lamp) is on, the technician should retrieve the Diagnostic Trouble Code (DTC) using a scan tool and follow the manufacturer's recommended procedure to diagnose the issue. In addition, all OBD II (On-Board Diagnostics) monitors should have the enable criteria achieved before a test is performed to ensure accuracy and reliability of the diagnostic information.

Question 7

The MIL is turned off under any of the following conditions, EXCEPT ________.
A) vehicle is driven on 3 consecutive trips with a warm-up cycle, without detecting a fault
B) power to the PCM is disconnected
C) PCM diagnostic link is grounded
D) codes are cleared with a scan tool

Accepted Answer

Grounding the PCM diagnostic link does not turn off the Malfunction Indicator Light (MIL); it is a method used for diagnostic purposes and does not directly affect the MIL status. Options A, B, and D are actions that can lead to the MIL being turned off, assuming no faults are detected or the conditions for turning off the light are met.

Question 8

Technician A says that OBD-II includes generic as well as vehicle manufacturer's specific DTCs and data displays. Technician B says that OBD-II have common DTCs. Who is right?
A) Technician A only
B) Technician B only
C) Both technicians A and B
D) Neither technician A nor B

Accepted Answer

Technician A is correct that OBD-II includes both generic and vehicle manufacturer-specific DTCs and data displays. Technician B is also correct that there are common DTCs that are the same across all vehicles with OBD-II systems. Therefore, both technicians are correct.

Question 9

A U type DTC indicates a problem with ________.
A) body and accessories
B) powertrain
C) communication related systems
D) suspension system

Accepted Answer

A U type Diagnostic Trouble Code (DTC) indicates a problem with communication related systems in a vehicle. These codes are used to identify issues with the network communication between the vehicle's electronic modules.

Question 10

An element of the OBD II diagnostic management system which stores engine data during a DTC set is called ________.
A) vehicle in vehicle out
B) memory account
C) misfire
D) freeze frame

Accepted Answer

The element of the OBD II diagnostic management system which stores engine data during a DTC set is called a freeze frame. Option A (vehicle in vehicle out) is not a recognized term in OBD II diagnostics, option B (memory account) is not a recognized term, and option C (misfire) is a type of DTC but not the term used for storing engine data during a DTC set.

Question 11

On-board diagnostic (OBD) systems I and II are being discussed. Technician A says that OBD II systems require misfire detection. Technician B says that OBD I was capable of detecting exhaust emission control system failures. Who is right?
A) Technician A only
B) Technician B only
C) Both technicians A and B
D) Neither technician A nor B

Accepted Answer

OBD II systems, introduced in the mid-1990s, are required to detect engine misfires as part of their comprehensive monitoring capabilities to ensure vehicles meet emissions standards. OBD I systems, which were the predecessors to OBD II, had more limited diagnostic capabilities and were not standardized across manufacturers. While OBD I systems could detect some issues that might affect emissions, they were not as advanced or consistent in their ability to diagnose exhaust emission control system failures specifically.

Question 12

In an OBD II system, when all enabling criteria for a given diagnostic is met, it's considered which of these terms?
A) A tuned engine
B) A trip
C) A warmed-up engine
D) A freeze frame

Accepted Answer

When all enabling criteria for a given diagnostic is met in an OBD II system, it's considered a trip. A trip is defined as the time period during which the vehicle is operating, and all the enabling criteria for a given diagnostic have been met.

Question 13

Technician A says that a warm up cycle is a trip where the engine reaches at least 160 degrees F. Technician B says that OBD II requires the diagnostic system to monitor all emission-related components and systems. Who is right?
A) Technician A only
B) Technician B only
C) Both technicians A and B
D) Neither technician A nor B

Accepted Answer

Technician A is correct in stating that a warm up cycle requires the engine to reach at least 160 degrees F. Technician B is also correct in stating that OBD II requires the diagnostic system to monitor all emission-related components and systems. Therefore, both technicians A and B are correct.

Question 14

Which organization(s) developed guidelines for OBD II?
A) EPA and CARB
B) CARB
C) DOT and EPA
D) EPA

Accepted Answer

EPA (Environmental Protection Agency) and CARB (California Air Resources Board) jointly developed the guidelines for OBD II (On-Board Diagnostics II) in order to regulate emissions from vehicles and ensure consistent monitoring and reporting of any malfunctions.

Question 15

Which of these is checked during an OBD II PCM initiated functionality test?
A) ECT
B) IAC
C) O2 sensor
D) Brake switch

Accepted Answer

The answer of Which of these is checked during an...

Question 16

A type C DTC will light the MIL.

Accepted Answer

A type C DTC (Diagnostic Trouble Code) is a temporary fault code that does not immediately light the Malfunction Indicator Lamp (MIL); it requires a certain number of fault occurrences before the MIL is illuminated.

Question 17

Setting a type B DTC will also trigger a freeze frame.

Accepted Answer

When a type B diagnostic trouble code (DTC) is set, a freeze frame is also created.

Quiz 10: Onboard Diagnosis

The OBD II task manager is responsible for ________.

freeze-frame data includes all of the following EXCEPT ________.

A vehicle has a flashing MIL when warmed up and driving. What does this mean?

A freeze-frame is a ________ of all data at the instant an emission-related DTC is set.

Enable criteria means ________.

Technician A says that when the MIL is on, the technician should retrieve the DTC and follow the manufacturer's recommended procedure to find the root cause of the problem. Technician B says that all OBD II monitors must have the enable criteria achieved before a test is performed. Who is right?

The MIL is turned off under any of the following conditions, EXCEPT ________.

Technician A says that OBD-II includes generic as well as vehicle manufacturer's specific DTCs and data displays. Technician B says that OBD-II have common DTCs. Who is right?

A U type DTC indicates a problem with ________.

An element of the OBD II diagnostic management system which stores engine data during a DTC set is called ________.

On-board diagnostic (OBD) systems I and II are being discussed. Technician A says that OBD II systems require misfire detection. Technician B says that OBD I was capable of detecting exhaust emission control system failures. Who is right?

In an OBD II system, when all enabling criteria for a given diagnostic is met, it's considered which of these terms?

Technician A says that a warm up cycle is a trip where the engine reaches at least 160 degrees F. Technician B says that OBD II requires the diagnostic system to monitor all emission-related components and systems. Who is right?

Which organization(s) developed guidelines for OBD II?

Which of these is checked during an OBD II PCM initiated functionality test?

A type C DTC will light the MIL.

Setting a type B DTC will also trigger a freeze frame.