Brakes

Before refinishing a hub-style rotor on an on-car brake lathe, you should:

Adjust the wheel bearing so there is no play

Which of the following is a main component of a typical hydraulic brake system?

All of the above- brake pedal, brake fluid, master cylinder

Combinations may contain the following:

All of the above- pressure differential valve, meterig valve, proportioning valve

Tech A says that during anti-lock braking, brake fluid may be returned to the master cylinder. Tech B says that solenoid valves in the hydraulic control unit will isolate the master cylinder from the brake circuit when it is in the "hold" mode. Who is correct?

Both

Tech A says that in a CAN-bus circuit the parking brake sensor and the low brake fluid sensors send signals over the CAN-bus network regarding their status. Tech B says that diagnosis involves using a scan tool capable of interrogating the system, a wiring diagram, and a DVOM to perform specific tests. Who is correct?

Both

Tech A says that in some cases, the electronic brake control module can be programmed with a new tire size to restore proper electronic brake control performance. Tech B says that there could be an electronic brake control module available for installation that matches a new tire size. Who is correct?

Both

Tech A says that wheel bearings can be damaged from hitting a large pothole. Tech B says that wheel bearings can be damaged from improper adjustment. Who is correct?

Both

Technician A says that a hydraulic press and a bearing race installer can be used to install a bearing race. Technician B says that a hammer and a bearing race installer can be used to install a bearing race. Who is correct?

Both

Technician A says that servicing the wheel bearings is a common part of a brake job if the vehicle has serviceable wheel bearings. Technician B says that if the vehicle uses non-serviceable bearings, the bearings should be checked during a brake job and replaced if they are worn out. Who is correct?

Both

Technician A says that the wheel bearing grease seal is designed to contain the lubricant. Technician B says that the wheel bearing grease seal is designed to keep out contaminants. Who is correct?

Both

Technician A says that to depressurize high-pressure components of the electronic brake control (EBC) system, research the procedure for depressurizing the accumulator in the service information. Technician B says to remove the ABS fuse from the fuse box and apply the brake firmly at least 40 times when depressurizing the components of the EBC system. Who is correct?

Both

Tech A says that disc brakes were originally developed in the early 1900's but didn't find common use until the 1960's. Technician B says that a disc brake operates by squeezing brake pads on both sides of a rotor or disc that is sttached to the wheel. who is correct?

Both A and B

Tech A says that the heavier the vehicle, the more stopping power is needed. Tech B says that the faster a vehicle is moving, the more braking power is needed. Who is correct?

Both A and B

Technician A says that the brake calipers use hydraulic pressure from the master cylinder to apply the brake pads. Technician B says that when the brake pedal is depressed, a push rod transfers force through a brake booster to a hydraulic master cylinder. Who is correct

Both A and B

Technician A says that force is transmitted hydraulically through the brake fluid. Technician B syas that by using cylinders of different sizes, forces can be increased or reduced, allowing designers to obtain the desired braking force for each wheel. Who is correct?

Both a and b

Parking brake cables transmit force from the parking brake actuating lever to the

Brake unit

After-market adjustable proportioning valves are not available for performance applications

False

Drum brakes are generally more expensive to manufacture and easier to adapt a parking brake to

False

If brake fluid boils, it turns from vapor to a liquid, which is compressible.

False

The booster chambers are separated by a (blank) diaphragm attached to the diaphragm plate.

Flexible rubber

All power brake systems should be inspected and tested for any of these reasons EXCEPT

If the vehicle has an intake manifold gasket leak.

The vacuum assisted power booster uses the difference between engine vacuum and atmospheric pressure to (blank) the force that acts on the master cylinder pistons.

Increase

In an ABS hydraulic control unit, the________________ and dump valves can be separate valves or they can be combined into a common assembly.

Isolation

A(n) (blank) brake (or compression brake) uses an extra lobe on the camshaft to control an auxiliary exhaust valve at the top of each cylinder.

Jake brake

Hydraulic lines and hoses connect the (blank) to the wheel brake units.

Master cylinder

Which brake is used for holding a vehicle in place when it is stationary?

Parking

Static friction is resistance between nonmoving surfaces and is present in which type of brakes?

Parking brakes

The pushrod transmits the brake pedal force directly to either the master cylinder or to the (blank)

Power booster

The (blank) valve is in the master cylinder or in a separate unit in the rear brake circuit, while the (blank) type is mounted on the body or on the axle, where it can respond to load changes.

Pressure-sensitive, Load-sensitive

(blank) are used on drum brake systems to maintain brake fluid pressure and prevent air entry when the brakes are off.

Residual pressure valves

When diagnosing a stop light system for the stop lights illuminating all the time (brake pedal not depressed), which of the following is LEAST likely to be the cause?

Short to ground

Some brake canisters incorporate a separate air chamber and large spring assembly. These are referred as

Spring brakes

Two students are discussing Newton's first law of motion. Student A says that a lightweight vehicle requires as much energy to accelerate as a heavier vehicle. Student B says that a lighter vehicle requires less energy to accelerate than a heavier vehicle. Who is correct?

Student B

Tech A says that a typical wheel speed sensor can be faulty due to a sensor resistance problem. Tech B says that a typical wheel speed sensor could be faulty due to no voltage supply. Who is correct?

Tech A

Tech A says that generally asphalt and concrete road surfaces allow for good braking. Tech B says that generally gravel or dirt road surfaces allow for good braking. Who is correct?

Tech A

Tech A says that the two different types of lubricants used to lubricate bearings cannot be substituted due to the different housing and seal designs each lubricant demands in a vehicle. Tech B says that the two different types of lubricants used to lubricate bearings can be substituted due to the different housing and seal designs each lubricant demands in a vehicle. Who is correct?

Tech A

Tech A says that traction control can reduce the power output of the engine to increase traction. Tech B says that electronic stability control increases the risk of rollover. Who is correct?

Tech A

Tech A states using an air-operated brake on heavy trucks is easier. Tech B states that using a hydraulic brake on a heavy truck is easier. Who is correct?

Tech A

Technician A says that fixed calipers are rigidly bolted in place and cannot move or slide. Technician B says that the sliding or floating calipers has pistons on both sides of the rotor.

Tech A

Technician A says that in some cases, the electronic brake control module can be programmed with a new tire size to restore proper electronic brake control performance. Technician B says that there could be a new brake power booster available for installation that matches a new tire size. Who is correct?

Tech A

Technician A states that the tone wheel used on an anti-lock braking system's wheel speed sensors should be checked for broken teeth. Technician B states that the tone wheel used on an anti-lock braking system's wheel speed sensors should be checked for surface rust. Who is correct?

Tech A

Tech A says that an ABS key-on system test checks for faults in the vehicle's base brake system. Tech B says that on most vehicles ABS DTCs are stored in memory for later retrieval. Who is correct?

Tech B

Tech A says that if you add pre-lube to a sealing lip of an axle seal, it will cause overheating during the initial use resulting in premature failure of the seal. Tech B says that when you install a seal, always remember to pre-lube the sealing lip with a small amount of oil or grease. Who is correct?

Tech B

Tech A states that the scrub braking system worked well in rubber tires. Tech B states that the scrub braking system worked reasonably well on dry wheel surfaces made of wood or steel. Who is correct?

Tech B

Technician A says that a center high-mount stop lamp (CHMSL) is used to apply the brakes in there is a brake failure. Technician B says that as of 1986, all vehicles must have a center high-mount stop lamp to reduce incidence of rear-end collisions. WHo is correct?

Tech B

Technician A says that a typical wheel speed sensor can be faulty due to worn out brake shoes. Technician B says that a typical wheel speed sensor could be faulty due to generating an improper sensor pattern. Who is correct?

Tech B

Two technicians are discussing Newton's first law of motion. Technician A says that a lightweight vehicle requires as much energy to accelerate as a heavier vehicle. Technician B says that a lighter vehicle requires less energy to accelerate than a heavier vehicle. Who is correct?

Tech B

Tech A says that a faulty vacuum booster can affect engine operation. Tech B says that steel brake line can be replaced with a copper line, since it is easier to bend into shape. Who is correct?

Tech a

The cause of the power booster not holding vacuum could be

The atmospheric valve at the front of the booster

Additional programming is added to the EBCM to control the high-pressure pump and extra HCU valves and to decide when each of them needs to be activated.

True

Each valve in a combination valve operates individually, as it was designed and is collected in one unit.

True

If mismatched tires are used on a vehicle with ESC, the EBCM may set a code and disable the system.

True

Some foot-mounted parking brake levers can be released by pulling a release handle, which retracts the ratcheting tang and allows the pedal to return to its rest position.

True

Some front axle housings on four-wheel drive vehicles use separate, sealed bearing chambers to hold a quantity of gear lube.

True

The brak pedal is usually suspended from a braket between the dash panel and the firewall.

True

The parking brake cable pulls on an actuating lever inside the brake drum assembly.

True

The power booster can be operated by engine vacuum or through hydraulic pressure. which is usually generated by the power steering pump or an electric-driven pump.

True

Which of the following components is NOT typically found on an electric brake system?

Wheel cylinder

The effectiveness of friction brakes depends n the braking components'

ability to dissipate heat quickly

Banjo fittings are made up of all the following except

banjo nut

Disc brake pads consist of friction material ________ or _________ onto a steel backing plate (disc brakes).

bonded, riveted

Tech A says that pistons plated with chrome resist rust. Tech B says that pistons made of phenolic resin do not corrode and rust. Who is correct?

both

Technician A says that you should always start lug nuts on the wheel stud by hand. Technician B says that on some vehicles, you are required to install the hubcap before installing the lug nuts. Who is correct?ed maliciously

both

technician A says that you should always start lug nuts on the wheel stud by hand. Technician B says that on some vehicles, you are required to install the hubcap before installing the lug nuts. Who is correct?ed maliciously.

both

If the brake pedal linkage is not adjusted correctly, brake fluid may not be able to expand back into the reservoir through the ________________ port of the master cylinder when the brakes get hot.

compensating

In regenerative braking, the amount of stopping power is controlled by the amount of

electricity generated

Just changing the master cylinder normally requires pushrod length adjustment

false

True or False. Pinching off the flexible brake hoses with vice grip pliers is a recommended method of closing rubber brake lines.

false

Disc brakes create stopping power by forcing

flat friction pads against a rotating disc

For hydraulic cylinders of the same size, the (blank) transmitted from one is the same value as the (blank) applied to the other.

force, force

Over time, the mechanical drum brake system gave way to the modern (blank) brake system beacuse of its ability to automatically equalize braking forces at each wheel.

hydraulic drum

A substantial leak in the (blank) will prevent enough pressure from building to exert the necessary braking force

hydraulic system

Dual-Diaphragm boosters apply, hold, and release _____ a single-diaphragm booster

in the same manner as

All the following are disadvantages to a jake brake except

increases brake effectiveness

Skidding tires on the surface of the road (kinetic friction) do not have as much friction as rolling tires, and therefore the stopping distance (blank), which can lead to an accident.

is increased

Different (blank) designs can be engineered to alter the brake pedal effort required of the driver by using different levels of mechanical advantage.

lever

A (blank) transfers hydraulic fluid through lines and hoses to the wheel brake units.

master cylinder

DVOM-galvanic test spec

more than 0.3 volts

Technician A says that vacuum boosters use only single diaphrgms to extract power from the atmospheric pressure and transmit force to the master cylinder. Technician B says that a one-way vacuum check valve is used to prevent brake fluid from entering the vacuum booster. Who is correct?

neither a or B

Tech A says that the metering valve controls pressure to the rear brakes. Tech B says that the proportioning valve controls pressure to the front brakes. Who is correct?

neither a or b

The principle behind hydraulic brakes is (blank), which states thatpressure applied to a fluid in one part of a closed system will be transmitted without loss to all other areas of the system.

pascals law

The rotational force found in a braking vehicle tends to

push the nose down and lift the rear

Most modern master cylinder reservoirs are equipped with a low brake fluid float switch that turns on the (blank) on the instrument panel and/or sets a notification on the driver information system.

red brake warning light

The best example of (blank) is when a motorcycle rider applies the front brake hard enough that the rear wheel is lifted completely off the ground.

rotational force

Wheel lug nuts should be properly torqued in the proper sequence to ensure that the:

rotors do not warp

At rest, the (blank) is open and connects the reservoir with the front brake circuits.

supply port

ech A says that calipers use a round section O-ring to seal each piston. Tech B says that calipers use a square section O-ring to seal each piston. Who is correct?

tech b

The hydraulic system components must be able to withstand the force, pressure, and (blank) generated in the hydraulic system.

temparatures

Part of the parking brake cable is inside a wound steel housing

true

true or false. to ensure that a leak in one brake circuit will not affect the other circuit, master cylinder reservoirs have two separate chambers.

true

Brake-by-wire means there is no mechanical or hydraulic connection betwenn the brake pedal and the

wheel brake units