Chapter 10

Question 1

Describe the general operation of a magnetic reluctance (PM) wheel speed sensor.

Answer 1

The PM wheel speed sensor is a variable reluctance sensor that produces a voltage directly related to the rotational speed of the wheel

Question 2

Describe the general operation of a magnetoresistive wheel speed sensor.

Answer 2

must have a 12 volt reference supplied to it by the Electronic Brake Control Module (EBCM). This voltage is modified to a changing frequency and sent back to the EBCM

Question 3

Explain the job of wheel speed sensors in the ABS system.

Answer 3

The wheel speed sensors signal the EBCM about the speed of the wheels during braking

Question 4

Describe the construction differences between the integrated ABS and the nonintegrated ABS.

Answer 4

In an integrated system the master cylinder is not replaceable without replacing the modulator

Question 5

Describe the difference in the DBC-7 without TCS and the DBC-7 with TCS.

Question 6

What can the Bosch ABS 9.0 unit control as far as braking/stability control enhancements?

Question 7

Explain why some ABS systems no longer use proportioning valves.

Question 8

What is the advantage of vehicle networking?

Question 9

What is the first thing the traction control can do to help eliminate positive wheel spin?

Question 10

If the EBCM senses wheel slip when the brakes are not applied, its first step is to request the PCM to reduce________ ________.

Answer 10

engine torque

Question 11

The DBC-7 operates on ______ volts instead of _______ volts.

Question 12

High-speed CAN, which is needed for “real time” computer interaction is rated at _______

Answer 12

1 Mb/second

Question 13

A slow wheel as monitored by the wheel speed sensor will produce a ________frequency signal, whereas a faster wheel will cause a comparatively _______ frequency.

Answer 13

lower, higher

Question 14

The ________ replaces the standard hydraulic proportioning valve found on many older vehicles.

Question 15

The magnetoresistive sensor produces a _______ signal and has its own power supply. The amplitude of the signal is constant.

Question 16

Magnetic lines of force are called ______ _______.

Question 17

The Continental Teves Mk60/Mk70 system has hydraulic brake assist that increases pressure to the brakes whenever a _______ ________ is detected through the brake pedal sensor.

Question 18

The hydraulic pump for the Bosch 9.0 system has ________ pistons instead of two that were used on earlier systems.

Question 19

The TCS is designed to control wheel spin or ________ wheel slip.

Question 20

Technician A says with digital signals only the frequency changes.

Technician B says an analog voltage signal is infinitely variable; in other words, it flows smoothly as it changes voltage levels.

Who is correct?

Question 21

Sensors are being discussed.

Technician A says that sensors are used to measure some sort of physical action and change it to an electrical signal.

Technician B says that the simplest sensors are often on–off switches.

Who is correct?

Question 22

Technician A says that an actuator converts mechanical action to electric energy.

Technician B says that an actuator uses electric current to perform a mechanical action.

Who is correct?

Answer 22

b

Question 23

Actuators and sensors are being discussed.

Technician A says that a too low current may mean that an actuator or sensor is not functioning properly.

Technician B says that the controller cannot monitor actuator and sensor operation electrically.

Who is correct?

Question 24

Command signals are being discussed.

Technician A says that automotive controllers (computers) are simple compared to those used at work or school.

Technician B says that most automotive computers work without sharing information with other computers on the network.

Who is correct?

Question 25

While discussing TCS as an outgrowth of four-wheel four-channel ABS,

Technician A says most of the same components are used in both systems.

Technician B says the TCS also interfaces with the engine (PCM) and transmission (TCM) control modules to request that specific actions be taken.

Who is correct?

Question 26

Technician A says that an integrated ABS unit has many serviceable parts.

Technician B says that the nonintegrated ABS has many serviceable parts.

Who is correct?

Question 27

There are several different names in use for the ABS controller. All of the following names have been used except:

BACU
ICU
EBCM
CAB

Question 28

While discussing ABS brakes,

Technician A says ABS is excellent in directional stability.

Technician B says ABS is excellent in directional control.

Who is correct?

Question 29

Technician A says that PM generator (variable reluctance) sensor produces a digital signal.

Technician B says that a PM generator used an electromagnet as part of the sensor.

Who is correct?