Question 1

When the concentration of oxygen on the exhaust side of the thimble is low (rich exhaust), a voltage of ________ is generated between the electrodes.

Accepted Answer

A)  0.60-1.0 
B)  1.0-2.0 
C)  0.25-0.50 
D)  10-20 
A)  0.60-1.0 
B)  1.0-2.0 
C)  0.25-0.50 
D)  10-20 A

Question 2

What does the post, or downstream, oxygen sensor (HO2S) measure?

Accepted Answer

A)  Amount of H2O in front of the catalytic converter 
B)  Amount of H2O behind the catalytic converter 
C)  Amount of oxygen in front of the catalytic converter 
D)  Amount of oxygen behind the catalytic converter 
A)  Amount of H2O in front of the catalytic converter 
B)  Amount of H2O behind the catalytic converter 
C)  Amount of oxygen in front of the catalytic converter 
D)  Amount of oxygen behind the catalytic converter D

Question 3

Technician A says that oxygen sensors can be tested using a test light or dwell meter, or a scan tool. Technician B says that conditions can occur that cause the oxygen sensor to be fooled and give a false lean or false rich signal to the PCM. Which technician is correct?

Accepted Answer

A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B 
A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B B

Question 4

In some hybrid electric vehicles, the wide band oxygen sensor can cause the PCM to enter closed loop ________.

Accepted Answer

A)  within 10 seconds of engine (IC
E)  start-up 
B)  as soon as the engine (IC
E)  starts 
C)  by the time the vehicle reaches 60 mph 
D)  within 2 minutes 
A)  within 10 seconds of engine (IC
E)  start-up 
B)  as soon as the engine (IC
E)  starts 
C)  by the time the vehicle reaches 60 mph 
D)  within 2 minutes

Question 5

A P0132 DTC is being discussed. Technician A says that a defective HO2S could be the cause. Technician B says that an HO2S signal wire shorted-to-ground could be the cause. Which technician is correct?

Accepted Answer

A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B 
A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B

Question 6

A heated Zirconia oxygen sensor will have how many wires?

Accepted Answer

A)  2 
B)  3 
C)  4 
D)  Either B or C 
A)  2 
B)  3 
C)  4 
D)  Either B or C

Question 7

With the vehicle in closed loop, the following post converter HO2S scope pattern activity is seen. What does this indicate?

Accepted Answer

A)  A lazy converter 
B)  A good converter 
C)  A bad converter 
D)  None of these 
A)  A lazy converter 
B)  A good converter 
C)  A bad converter 
D)  None of these

Question 8

The two internal chambers of a dual cell wide band oxygen sensor include ________ and ________.

Accepted Answer

A)  inside; outside 
B)  single; dual 
C)  air reference; diffusion 
D)  Nernst; Pump 
A)  inside; outside 
B)  single; dual 
C)  air reference; diffusion 
D)  Nernst; Pump

Question 9

When the air/fuel ratio is expressed as lambda, a lambda number of less than 1 indicates a(n) ________ exhaust.

Accepted Answer

A)  rich 
B)  excessively cold 
C)  lean 
D)  excessively hot 
A)  rich 
B)  excessively cold 
C)  lean 
D)  excessively hot

Question 10

Technician A says that an oxygen sensor produces a voltage output signal based on the oxygen content of the exhaust stream. Technician B says that if the exhaust has little oxygen the voltage of the oxygen sensor will be close to 0 volts. Which technician is correct?

Accepted Answer

A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B 
A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B

Question 11

With the vehicle in closed loop, the following post converter HO2S scope pattern activity is seen. What does this indicate?

Accepted Answer

A)  A lazy converter 
B)  A good converter 
C)  A missing converter 
D)  A bad converter 
A)  A lazy converter 
B)  A good converter 
C)  A missing converter 
D)  A bad converter

Question 12

On a poorly running engine, the wide band oxygen sensor can be quickly checked by ________.

Accepted Answer

A)  disconnecting the vehicle battery 
B)  disconnecting the sensor connector 
C)  jumping the connector with a jumper wire 
D)  jumping the connector with a flashlight battery 
A)  disconnecting the vehicle battery 
B)  disconnecting the sensor connector 
C)  jumping the connector with a jumper wire 
D)  jumping the connector with a flashlight battery

Question 13

Technician A says that oxygen sensors can have one, two, three, four, or more wires, depending on the style and design. Technician B says that if the exhaust has little oxygen, the voltage of the oxygen sensor will be close to 1 volt (1000 mV) and close to zero if there is high oxygen content in the exhaust. Which technician is correct?

Accepted Answer

A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B 
A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B

Question 14

A P0131 DTC is being discussed. Technician A says that an exhaust leak upstream of HO2S (bank 1) oxygen sensor could be the cause. Technician B says that an extremely rich air-fuel mixture could be the cause. Which technician is correct?

Accepted Answer

A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B 
A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B

Question 15

A large amount of oxygen in the exhaust system causes the O2S (Oxygen sensor) to produce which of these?

Accepted Answer

A)  High voltage 
B)  Abnormal readings 
C)  Low voltage 
D)  False readings 
A)  High voltage 
B)  Abnormal readings 
C)  Low voltage 
D)  False readings

Question 16

The sensor that must be warmed and functioning before the engine management computer will go to closed loop is the ________.

Accepted Answer

A)  O2S 
B)  ECT sensor 
C)  BARO sensor 
D)  MAP sensor 
A)  O2S 
B)  ECT sensor 
C)  BARO sensor 
D)  MAP sensor

Question 17

Most service information specifies that a(n) ________ be used when testing a wide band oxygen sensor.

Accepted Answer

A)  vacuum hose 
B)  generic scan tool 
C)  HO2S disconnect bypass tool 
D)  factory scan tool 
A)  vacuum hose 
B)  generic scan tool 
C)  HO2S disconnect bypass tool 
D)  factory scan tool

Question 18

Technician A says that a wide-band oxygen sensor, also called a lean air-fuel (LAF) sensor, can detect air-fuel ratios from as rich as 10:1 to as lean as 23:1. Technician B says that the oxygen sensor signal determines fuel trim which is used to tailor the air-fuel mixture for the catalytic converter. Which technician is correct?

Accepted Answer

A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B 
A)  Technician A only 
B)  Technician B only 
C)  Both technicians A and B 
D)  Neither technician A nor B

Question 19

When testing an oxygen sensor using a DSO (digital storage oscilloscope), how quickly should the voltage change when either propane is added to the intake stream or when a vacuum leak is created?

Accepted Answer

A)  Less than 100 ms 
B)  100-200 ms 
C)  450-550 ms 
D)  1-3 seconds 
A)  Less than 100 ms 
B)  100-200 ms 
C)  450-550 ms 
D)  1-3 seconds

Question 20

Where is sensor 1, bank 1 located?

Accepted Answer

A)  On the same bank where number 1 cylinder is located 
B)  In the exhaust manifold 
C)  On the bank opposite cylinder number 1 
D)  Both A and B 
A)  On the same bank where number 1 cylinder is located 
B)  In the exhaust manifold 
C)  On the bank opposite cylinder number 1 
D)  Both A and B

Exam 19: Oxygen Sensors

When the concentration of oxygen on the exhaust side of the thimble is low (rich exhaust), a voltage of ________ is generated between the electrodes.

What does the post, or downstream, oxygen sensor (HO2S) measure?

Technician A says that oxygen sensors can be tested using a test light or dwell meter, or a scan tool. Technician B says that conditions can occur that cause the oxygen sensor to be fooled and give a false lean or false rich signal to the PCM. Which technician is correct?

In some hybrid electric vehicles, the wide band oxygen sensor can cause the PCM to enter closed loop ________.

A P0132 DTC is being discussed. Technician A says that a defective HO2S could be the cause. Technician B says that an HO2S signal wire shorted-to-ground could be the cause. Which technician is correct?

A heated Zirconia oxygen sensor will have how many wires?

With the vehicle in closed loop, the following post converter HO2S scope pattern activity is seen. What does this indicate?

The two internal chambers of a dual cell wide band oxygen sensor include ________ and ________.

When the air/fuel ratio is expressed as lambda, a lambda number of less than 1 indicates a(n) ________ exhaust.

Technician A says that an oxygen sensor produces a voltage output signal based on the oxygen content of the exhaust stream. Technician B says that if the exhaust has little oxygen the voltage of the oxygen sensor will be close to 0 volts. Which technician is correct?

With the vehicle in closed loop, the following post converter HO2S scope pattern activity is seen. What does this indicate?

On a poorly running engine, the wide band oxygen sensor can be quickly checked by ________.

A P0131 DTC is being discussed. Technician A says that an exhaust leak upstream of HO2S (bank 1) oxygen sensor could be the cause. Technician B says that an extremely rich air-fuel mixture could be the cause. Which technician is correct?

A large amount of oxygen in the exhaust system causes the O2S (Oxygen sensor) to produce which of these?

The sensor that must be warmed and functioning before the engine management computer will go to closed loop is the ________.

Most service information specifies that a(n) ________ be used when testing a wide band oxygen sensor.

When testing an oxygen sensor using a DSO (digital storage oscilloscope), how quickly should the voltage change when either propane is added to the intake stream or when a vacuum leak is created?

Where is sensor 1, bank 1 located?

The Diagnostic Process

Gasoline, Alternative Fuels, and Diesel Fuels

Circuit Testers and Digital Meters

Oscilloscopes and Dsos

Engine Systems

In-Vehicle Engine Service

Valve Train and Variable Valve Timing Diagnosis

Engine and Misfire Diagnosis

Can and Network Communications

Onboard Diagnosis

Global Obd Ii and Mode 06

Immobilizer Systems

Starting and Charging System Diagnosis

Ignition System Operation and Diagnosis

Temperature Sensors

Throttle Position Tp Sensors

Map and Maf Sensors

Electronic Throttle Control Systems

Fuel Trim Diagnosis

Fuel Pumps, Lines, and Filters

Fuel-Injection Components and Operation

Gasoline Direct-Injection Systems

Fuel-Injection System Diagnosis and Service

Electronic Transmission Controls

Vehicle Emissions Standards and Testing

Emission Control Devices Operation and Diagnosis

Module Reprogramming

Symptom-Based Diagnosis

Filters

With the vehicle in closed loop, the following post converter HO₂S scope pattern activity is seen. What does this indicate?

The two internal chambers of a dual cell wide band oxygen sensor include and .

With the vehicle in closed loop, the following post converter HO₂S scope pattern activity is seen. What does this indicate?