Brakes A5 book questions
.1 A customer complains that a brake pedal is hard to depress. Technician A says it could be a plugged master cylinder replenishing port. Technician B says it could be excessive clearance between the master cylinder push rod and the master cylinder piston. Who is right? 2. A. Aonly B. Bonly C. Both Aand B D. Neither A nor B
1 Only Technician A is correct. A plugged replenishing port will cause a hard pedal. Technician B is wrong; excessive clearance between the master cylinder push rod and the master cylinder would not cause a hard pedal or braking effort. The correct answer is A.
12. Technician A says a proportioning valve is installed in the hydraulic line to the front brakes. Technician B says a metering valve is used with disc/drum brake sys- tems to keep the front discs from operating until the rear drums have started to work. Who is right? A. Aonly B. Bonly C. Both Aand B D. NeitherAnorB
12. Technician A is wrong. A proportioning valve is a brake system valve that maintains the correct proportion between the front and rear brake lines to provide a balanced vehicle braking system. Technician B is right; a metering valve is used with disc/drum brake systems to keep the front brakes from operating until the rear brakes have time to apply. The correct answer is B.
14. While testing a combination valve warning switch, as shown, the warning switch did not come on, but it does come on when a jumper wire is connected to a ground. Technician A says replace the valve. Technician B says the warning switch portion of the combination valve has malfunctioned. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
14. Both are correct. Since the combination valve contains all of the units to accomplish all of its tasks, the unit is replaced as a whole and is not rebuilt. The bottom line is that the valve needs to be replaced even if it is just the switch portion that is bad. The correct answer is C.
28. During an inspection of the disc brakes, the pads are observed to be worn to the backing pads. Technician A says the shoes will have to be replaced. Technician B says the rotor should be checked with a micrometer against the manufacturer's specifications. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither A nor B
28. Both technicians are right. If the pads are worn to their backing plates, the pads should be replaced and the rotor checked for excessive wear, parallelism, and scoring. The correct answer is C.
3. As shown, the vacuum booster pushrod length must be adjusted during all of the following repairs EXCEPT: A. brake shoe replacement. B. original assembly at the factory. C. master cylinder service. D. vacuum booster service
3. The vacuum booster pushrod length must be adjusted during the original assembly at the factory by the manufacturer, master cylinder service, and vacuum booster service. It is not of concern when you are replacing brake shoes; therefore, answer choice Ais wrong and A is the correct answer.
30. A vehicle with a front/rear split brake system is b e i n g discussed. Technician A says when a caliper is found to be scored beyond repair due to contaminated fluid just the contaminated caliper should be replaced. Technician B says when a caliper is found to be unrepairable both calipers on that axle set should be replaced. Who is right? A. Aonly B. B only C. BothAandB D. Neither Anor B
30. Technician A is wrong; if a caliper is scored beyond repair due to contaminated fluid the entire sys-tem should be inspected and flushed. If the fluid damaged one bore, it could have damaged them all. Technician Bis correct. Calipers should be replaced in pairs. The correct answer is B.
32. Brake rotors should be refinished under all of the following conditions EXCEPT: A. installation of a new brake rotor. b. . failure of lateral r u n o u t or thickness variation checks. C. noticeable brake pulsation D. heatspotsorslightscoring.
32. New brake rotors should not be refinished; therefore answer A is wrong. However, because this is an except-type question, the correct answer is A. Rotors should be refinished when there is lat- eral runout, thickness variation, pedal pulsations, heat spots, and light scoring.
33. A front brake rotor, shown in the figure, cannot be pulled off of the vehicle with the caliper positioned aside and the attaching hardware removed. Technician A says to apply penetrating fluid to the front and rear mating surfaces and then strike it between the studs with a rubber or plastic hammer. Technician B says to use a three-jaw puller. Who is right? A. Aonly B. Bonly C. Both A and B D. Neither A nor B
33. Both technicians are right. If a rotor is difficult to remove, penetrating oil can be sprayed onto the front and rear mating surfaces and the rotor knocked off with a soft-tipped mallet. If penetrating fluid gets on the rotor, the rotor must be replaced. Another acceptable way to remove a rotor is with a three-jaw puller. The correct answer is C.
6. When bench bleeding a master cylinder using brake tubing, it is important that the ends of the tubes are submerged as shown in the figure because A. It allows you to retain the expelled fluid. B. It keeps the master cylinder cups from swelling. C. It prevents contamination of the brake fluid. D. It prevents air from being sucked back into the master cylinder.
6. The reason for making sure the tubes remain submerged during benchbleedinga mastercylinder is simply to prevent the tubes from drawing in air as the pistons of the master cylinder are being moved. The correct answer is D.
8. Which of the following is true about flare nuts? A. They are only used ondouble flared brake tubing. B. They are highly resistant to rust and corrosion. C. Cleaning the ends of the hoses prior to removal will reduce D. They are only available in conventional sizes.
8. There is only one valid statement in this question; choice B. Flare nuts are highly resistant to rust and corrosion. The other statements are wrong. The correct answer is B.
Technician A says there are two types of brake line flares: double and single. Technician B says there is only one acceptable type of tubing flare: the ISO flare. Who is right? A. Aonly B. Bonly C. BothAand B D. Neither A nor B
9. This is an except-type question. AlL of the statements are true except choice Dand the correct answer is D. Replacement hoses should always match the size of the original equipment.
After a brake application, the caliper piston is returned by: A. thetwistingactionoftheseal. B. a return spring. C. brake fluid pressure. D. atmospheric pressure. (C.2) (C.7)
A
After honing a brake caliper, the maximum allowable increase in caliper bore diameter is: 41. A. 0.001 in (0.025 mm). B. 0.002 in (0.050 mm). C. 0.005 in (0.127 mm). D. 0.008 in (0.043 mm). (C.7)
A
An ABS-equipped rear-wheel-drive vehicle experiences lockup on both rear wheels during the anti-lock brake mode. Technician A says larger than specified tires may be installed on the rear wheels. Technician Bsays the rear tires may not be the same size on each rear wheel. Who is right? A. A only B. Bonly C. BothAandB D. Neither A nor B
A
Brake systems contain all of the following components EXCEPT: A. double wall copper tubing. B. high pressure rubber tubing. C. double wall steel tubing. D. flarenuts.
A
On ABS systems with a high-pressure accumulator, the accumulator i sdepressur- ized by: A. pumping the brake pedal 25 times with the ignition switch off. B. pumping the brake pedal 10 times with the ignition switch on. C. loosening the bleeder screw on the accumulator with the ignition switch on. D. loosening the front wheel bleeder screws with the ignition switch on
A
On a single piston floating caliper, the inside brake pad lining is worn out, but there is very little wear on the outside pad lining. The cause of the problem could be: A. worn caliper pins and bushings. B. a leaking caliper piston seal. C. a leaking brake hose. D. excessive rotor lateral runout. (C.7)
A
Technician A says the brake shoes shown in the figure are being adjusted to match the brake drum size. Technician B says the brake shoes are being measured for wear. W h o is right? A. Aonly B. Bonly C. Both Aand B D. Neither A nor B
A
Technician Asays that any time the brake lines are disconnected (or loosened) from the master cylinder, it has to be bled. Technician B says any time the brake system is worked on, the master cylinder must be bled. W h oi s right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
A
The brake warning light is illuminated continually with the ignition switch on in the above figure. Al of these defects may be the problem EXCEPT: A. an open circuit in the wire to the parking brake switch. B. the wire to the parking brake switch touching the vehicle ground. C. a continually closed parking brake switch. D. low fluid level in the secondary section of the master cylinder reservoir. (E.5)
A
The operation of ab r a k e system failure switch is being discussed. Technician A says the light comes on when there is a pressure difference on one side of the switch. Technician Bsays the light comes on when pressure is the same on both sides of theswitch. Who is right? A. Aonly B. Bonly C. Both A and B D. Neither A nor B
A
There are signs of paint removal and peeling on the power brake booster right below the master clinder. The cause of this could be: A. A leaking secondary cup o n the primary piston. B. A defective diaphragm in the brake booster. C. A leaking secondary cup on the secondary piston. D. Fuel being drawn into the booster by the vacuum.
A
When installing a new brake rotor: Technician A cleans any oil film from the sur- face of the rotor with solvent. Technician B does a finish cut on the rotor prior to installing it. Who is right? A. Aonly B. Bonly C. Both A and B D. Neither Anor B
A
While checking the vacuum supply to the power brake booster, Technician A says the vacuum gauge should be connected between the one-way check valve and the brake booster. Technician Bsays with the engine idling, the vacuum supplied to the brake booster should be 8 to 10 in Hg (74.4 to 67.6 kPa absolute). Who is right? A. Aonly B. Bonly C. Both Aand B D. NeitherAnorB
A
While discussing parking brake adjustments, Technician A says the brake shoes should be properly adjusted before the parking brake adjustment. Technician B says after the cable adjusting nut is tightened so the rear wheels have a slight drag, loosen the nut four turns. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither Anor B
A
While discussing wheel and lug nut installation, Technician Asays excessive lug nut torque may cause rotor runout. Technician Bsays an impact wrench may be used to tighten lug nuts. Who is right? A. Aonlv B. Bonly C. Both Aand B D. NeitherAnorB
A
35. After the brakes have been bled and the system refilled, the next thing that should be done is: A. Back off the drum brake star adjusters one full turn to avoid brake drag. B. Road test t h e vehicle. C. Pump the brakes several times and check for leaks. D. Move the vehicle back and forth several times applying the pedal hard to set t h e b r a k e self-adiusters.
After the brakes have been bled and the system refilled, the next thing that should be done is road test the vehicle. Bleeding should only be done after everything is installed and adjusted. T h e cor- rect answer is C.
7. After installing a bench bled master cylinder, Technician A says the entire system should be bled. Technician B says the system is ready for operation because the lines were capped. Who is right? A. Aonly B. Bonly C.BothAandB D. Neither A nor B
AlL bench bleeding accomplishes is the removal of air from the master cylinder. Therefore it is pos- sible that the system has air in it. In fact, it probably does even though the lines were capped. It is impossible to disconnect the lines and avoid letting some air in. Only Technician A is right and the correct answer is A.
2. A fast-fill valve is a valve assembly that provides brake fluid to what area? A. The reservoir B. The spool area of the secondary piston C. The spool area of the primary piston D. The master cylinder outlet port
Answer A is wrong; the purpose of the fast-fill valve is to rapidly fill the spool area of the primary piston with fluid from the reservoir. B is also wrong. The fast-fill valve is located between the pri- mary piston and the reservoir. Answer C is correct. The spool area of the secondary piston is the area that is provided fluid by the fast-fill valve. Answer D is wrong.T h e correct a n s w e r is C.
67. A diagnostic trouble code (DTC) representing the L/R wheel speed sensor is obtained in the ABS. This DTC may be caused by: A. an open circuit at R/R wheel signal low connected to the ABS module. B. a grounded circuit on the L/R wheel signal low connected to the ABS module. C. a larger tire than specified by the manufacturer on the L/R wheel. D. an open circuit in the electronic brake contro
B
A front-wheel-drive vehicle has tapered roller bearings in the rear wheel hubs. While adjusting the rear wheel bearings, the bearing adjustment nut is tightened to 25 ft. Ibs. (33.9 Nm).The bearing nut should then be: A. loosened one turn and then tightened to 50 in. Ib. (57.6 cm-kg). B. loosened one and one-half turn and tightened to 75 in. Ib. (86.4 cm-kg). C. loosened one half turn and tightened to 10 to 15 in. Ib. (11.5 to 17.3 cm-kg). D. loosened one half turn and tightened to 40 in. lb. (
B
A vehicle experiences poor stopping, and the pedal feels springy and spongy dur- ing brake application. Technician A says the vents in the master cylinder cover may be plugged. Technician B says there may be air in the hydraulic system. Who is right? A. Aonly B. Bonly C. Both Aand B D. NeitherAnorB
B
A vehicle has no brake pedal free play. This problem m a ycause: A. a low brake pedal. B. pressure build-up and dragging brakes. C. a spongy brake pedal. D. fluid leaking past the primary piston cups.
B
A vehicle pullst o the left during a brake application. The cause of the problem could be: A. The right front brake linings are contaminated with grease. B. The piston is seized in the right front brake caliper. C. The master cylinder pistons are swollen from contaminated fluid. D. The secondary compensating port is plugged in the master cylinder.
B
Al of these statements about rotor machining are true EXCEPT: A. A vibration damper must be placed around the outside diameter of the rotor to prevent chatter marks. B. With fixed caliper rotors, unequal amounts of metal may be machined from each side of the rotor. C. Machine both sides of the rotor before removing it from the rotor lathe. D. Use a sanding pad to sand the rotor surfaces after machining is completed.
B
All of the following statements are true about brake drum inside diameter mea- surements with a brake drum micrometer EXCEPT: A. The drum should be cleaned before measuring the diameter. B. If the drum diameter is less than specified, replace the drum. C. The diameter should be measured at twolocations around the drum. D. The drum diameter variation should not exceed 0.0035 in (0.009 mm)
B
All of these statements about bleeding an ABS with a high-pressure accumulator are true EXCEPT: Reservoir Main valve plug Valve block connector A. The front and rear brakes may be bled with a pressure bleeder. B. Be sure the ignition switch is on when using a pressure bleeder. C. Be sure the brake pedal is released when using a pressure bleeder. D. The rear brakes may be bled with a fully charged accumulator. (F.7)
B
During a surge bleeding procedure: A. The end of the bleeder hose must be kept above the level of the fluid in the container. B. Pump the pedal quickly several times with the bleeder screw closed. C. Pump the pedal quickly several times while opening the bleeder screw. D. Decrease the pressure bleeder chamber pressure to 10 psi (69 kPa). (A.4.1)
B
Excessive brake pedal pulsation is experienced while braking. Technician Asays the outer constant velocity joint may be worn. Technician B says the front wheel bearing may be worn and loose. Who is right? A. Aonly 37. B. B o n l y C. Both A and B D. Neither A nor B
B
In most cast iron master cylinders, the distance from the brake fluid level to the top of the reservoir casting should be: A. 0 in (0mm). B. 0.25 in (6.35 mm). C. 0.75 in (19 mm). D. 1.00 in (25.4 mm).
B
In the figure what does the part labeled as "A" represent? A. The point of the parking brake pedal assembly that should be lubricated. B. The hole where a specified pin should be installed when the parking brake cable is adiusted. C. The mounting point for the parking brake lamp. D. The point at which the parking brake should be fully applied. (E.4)
B
On a vehicle with front disc and r e a rdrum brakes, a scraping noise is present in one front wheel while braking. The cause of this problem could be A. worn caliper pins and bushings. B. the pad wear sensor contacting the rotor. C. loosecalipermountingbolts. D. a loose pad mounting in the caliper.
B
On an integral ABS with a high-pressure accumulator, all of these statements about accumulator pressure and p u m p run time are true EXCEPT: A. If the accumulator pressure is low, the pump run time may be longer than specified. B. Low accumulator pressure has n o effect o n brake boost power. C. A defective pressure switch may cause higher than specified boost pressure. D. A pressure gauge and adapter may be installed between the accumulator and the accumulator fluid passage. (F.8)
B
Refer to the illustration. Technician A says if component number 17 is omitted during brake hardware assembly, the brake will grab on the wheel. Technician B says if item number 8 is omitted during brake assembly, there will be no self- adjusting action. W h o is right? A. Aonly B. Bonly C. Both A and B D. NeitherAnorB
B
The power steering operates normally on a hydro-boost-equipped vehicle. During a hydro-boost brake test, the brake pedal is pumped several times with the engine not running. When medium pressure is applied to the brake pedal and the engine is started, the brake pedal height remains unchanged. Technician A says the power steering pump pressure may be low. Technician Bsays the accumulator may be defective in the hydro-boost unit. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither Anor B
B
There is evidence of brake fluid leakage into the engine. The cause of the problem could be: A. a defective vacuum hose to the brake booster. B. a defective one-way check valve in the booster vacuum hose. C. a defective P C valve with excessive restriction. D. a partially restricted air cleaner element.
B
When the brake pedal is depressed, the rear stoplights are not illuminated, but the high mount stoplight operates normally (see the preceding figures). The turn sig- nals and hazard warning circuits operate normally. Technician A says the cause of this problem may be a blown stop-hazard fuse. Technician B says there may be an open circuit between Junction S206 and the turn signal switch. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
B
While discussing ABS trouble codes: Technician Asays all vehicles with ABS pro- vide a means to display flash codes. Technician B says the use of a larger tire may affect ABS operation but will not set a DTC. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
B
While discussing a vehicle with dragging brakes, Technician A says fluid may be leaking past the master cylinder cups. Technician B says the stoplight and cruise control switch may require adjusting. Who is right? control switch may require adjusting. Who is right? a. aA only B. Bonly C. Both A and B D. Neither A nor B
B
While discussing brake backing plates, Technician A says a bent backing plate may cause brake grabbing. Technician B says a loose anchor bolt may cause brake chat- ter. Who is right? A. Aonly B. Bonly C. Both A and B D. Neither Anor B
B
While discussing brake fluids, Technician A says silicone-based brake fluids are hydroscopic. Technician B says DOT 3 and DOT 4 brake fluids tend to absorb moisture. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
B
While discussing brake lines, Technician A says a damaged brake line may be repaired with a short piece of line and compression fittings. Technician B says the necessary brake line bends should be made with a tubing bending tool. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither A nor B
B
While discussing brake pad installation, Technician A says the inboard and out- board brake pads are interchangeable in many calipers. Technician B says brake pad rattle may occur if there is any clearance between the pad retainer and the caliper retainer ledge. Who is right? A. Aonly B. Bonly .C BothAandB D. Neither Anor B (C.2)
B
While discussing pressure brake bleeding, Technician A says the metering valve should be closed. Technician Bsays the pressure bleeder has an air chamber below the fluid chamber, and a diaphragm that separates the fluid and air chambers. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither A nor B
B
While machining a brake drum: A. Tool chatter marks may be caused by excessive damping belt tension. B. The tool bit depth for a rough cut should be 0.005 to 0.010 in (0.127 to 0.254 mm). C. The tool bit depth for a rough cut should be 0.010 to 0.020 in (0.254 to 0.508mm). (B.3) (B.4) D. The tool bit depth for a finish cut should be 0.008 to 0.010 in (0.203 to 0.127 mm)
B
While reassembling a brake caliper: A. The boot should be installed and seated, followed by the seal. B. Coat the piston seal and boot with clean brake fluid. C. Leave the piston dry and install it through the boot and seal until it bottoms. D. Plug the bleeder screw hole and the high pressure inlet while installing the piston.
B
4.A customer is concerned that the brake pedal is easily depressed with little or no effect. Technician A says there could be air in the system and it should be bled. Tech- nician Bsays it could be a leaking primary cup in the master cylinder. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
Both technicians are correct. Both of these problems could cause the concern and both should be checked. The correct answer is C.
39. While testing the vacuum brake booster, the engine is operated for two minutes and then shut off. The brake pedal is then applied normally several times; the pedal goes down normally each time. Technician A says this indicates the booster is operating normally. Technician B says the one-way check valve is defective and should be replaced. W h o is right? A. Aonly B. Bonly C. BothAandB D. Neither Anor B
Both technicians are wrong and t h e correct a n s w e r is D. Technician A is wrong because after pumping the brakes with the engine off, the brake pedal effort should be harder. Technician Bis wrong because the one-way check valve has the purpose of keeping vacuum in the booster. The problem seems to be low vacuum at the booster.
34. Technician A says that regardless of the depth of the cut a brake rotor requires, it should be made in one pass. Technician B says the rotor should be sanded so it becomes directional in order to speed the seating of the brake pads. Who is right? A. Aonly B. Bonly C. Both A and B D. NeitherAnorB
Both technicians are wrong. Each pass on the lathe should remove no more than 0.015 in. (0.381 mm). If more metal must be removed, then two or more shallow cuts are needed. Sanding the rotors accomplishes little. T h e correct a n s w e r is D.
Which of the following is true about DOT 4 brake fluid? A. It's purple. B. It's compressible. C. It has a lower boiling point than DOT 3. D. It has a higher boiling point than DOT .3
Both technicians are wrong. The double flare and ISO flare are only used in brake line fabrication. Single flares are never used in brake line work. The double flare can also be used in brake line fabri- cation. The correct answer is D.
25. A vehicle experiences brake squeal during brake application. Technician A says t h e drums may be distorted. Technician Bsays the backing plates may be bent. Who is right? A.Aonly B. Bonly C. Both Aand B D. Neither A nor B
C
6. When servicing the integral ABS unit with a high-pressure accumulator, as shown in the figure, Technician A says the accumulator pressure should be relieved before removing the solenoid valve body. Technician B says the accumulator pressure should be relieved before removing the reservoir. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
C
A metering valve delays pressure to which set of brakes under which braking condition A. The rear brakes under light braking B. The rear brakes under heavy braking C. The front brakes under light braking D. The front brakes under heavy braking (A.3.1)
C
After the master cylinder is bled and installed, excessive brake pedal effort is required for brake application. Technician A says the vacuum hose connected to the brake booster may be restricted. Technician B says there may be insufficient clearance between pushrod and piston that allows pressure to build up in the sys- tem. Who is right? A. Aonly 9. B. Bonly C. Both A and B D. Neither A nor B
C
Al of these conditions may cause illumination of the red brake warning light EXCEPT: A. parking brake engagement. B. low fluid level in the master cylinder. C. an open wheel speed sensor winding. D. an accumulator pressure below 1,500 psi
C
Al of these statements about manual brake bleeding procedures are true EXCEPT: A. A hose is connected to the bleeder screw, and the opposite end of this hose is submerged in a container of brake fluid. B. Apply the brake pedal with moderate pressure and then open the bleeder screw. C. When the bleeder screw is opened and the pedal goes to the floor, release the pedal and close the screw. D. Repeat the bleeding procedure until the fluid escaping from the bleeder hose is free of air bubbles.
C
All of these defects may cause a car to pull to one side while braking EXCEPT: A. wrong or loose brake pads. B. loose caliper mounting bracket. C. seized master cylinder piston. D. sticking caliper pistons.
C
All of these statements about vacuum brake bleeding are true EXCEPT: A. The vacuum p u m p handle should be operated 10 to 15 times before the bleeder screw is opened. B. The vacuum pump creates a vacuum in the pump reservoir. C. The bleeder screw should be opened until there is approximately 1 in (25 mm) of brake fluid in t h e reservoir. D. Aoneway check valve is required in the line from the bleederscrewtothe reservoir.
C
The pressure gauges connected to the proportioning valve input and output in the figure should indicate: A. higher pressure at the output compared to the inlet during a moderate brake application. B. the same pressure at the input and the output during am o d e r a t e brake application. C. lowerpressureattheoutputcomparedtotheinputduringamoderatebrake application. D. lower pressure at the output compared to the input during a light brake application.
C
When adjusting the parking brakes on a vehicle equipped with rear disc brakes: A. Do nothing because the parking brakes are self-adjusting. B. There should be 0.75 in (19 mm) of slack in the cables so they don't bind dur- ing application. .C The parking brake cable should be adjusted with the parking brake on one click so there will be a slight drag in the wheels. D. The parking brake cable should be adjusted so there is 0.50 in (1.27 mm) between the stopper pin and the stop.
C
When making final adjustments on the drum brakes: A. The star adjuster should be adjusted until there is a slight drag on the wheel. B. The star adjuster should be adjusted until the shoes hold the wheel firmly in place and then backed off until there is a slight drag on the wheel. C. The star adjuster should be adjusted until there is a slight drag on the drum and then backed off until the wheel spins freely. D. The star adjuster should be adjusted one full turn to back the shoes further away f
C
While assembling the brake shoes and related hardware: A. The secondary shoe faces toward the front of the vehicle. B. The primary and secondary shoe return springs are interchangeable. C. Theadjustermustbeinstalledintheproperdirection. D. The adjuster cable usually is mounted on the primary shoe. (B.2) (B.7)
C
While discussing ABS service, Technician Asays the high-pressure accumulator must be discharged before a brake line is disconnected. Technician B says some manutacturers recommend relieving the accumulator gas pressure before accumu- lator disposal. Who is right? A. Aonly B. B o n l y C. BothAandB D. NeitherAnorB
C
While discussing brake hardware service, Technician A says dry shoe ledges on the backing plates may cause a squeaking noise during brake application. Technician B says slightly scored shoe ledges on the backing plates may be resurfaced and lubri- cated with high-temperature grease. Who is right? A. Aonly B. Bonly .C BothAandB D. Neither A nor B
C
While servicing a wheel cylinder: A. The parts should be washed in a soap and water solution. B. If the cylinder is pitted or deeply scored, hone the wheel cylinder. C. The piston cups should be lubricated with clean brake fluid before installation. D. During assembly, the flat side of the pistons face the brake shoe links.
C
With the engine running and the brake pedal applied and held with medium foot pressure, the brake pedal slowly moves downward. Technician A says brake fluid may be leaking past the master cylinder piston cups. Technician B says brake fluid may be leaking from a brake hose at one of the front wheels. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
C
With the engine stopped, the technician pumps the brake pedal several times and then holds the brake pedal o n and starts the engine. The pedal moves slightly downward when the engine is started. This action indicates: A. a restriction in the power booster vacuum hose. B. a defective check valve in the power booster vacuum hose. C. a normal vacuum supply to the power booster. D. a low intake manifold vacuum.
C
On an integral ABS with a high-pressure accumulator, Technician A says the mas- ter cylinder fluid level should be checked with a discharged accumulator. Techni- cian B says the master cylinder fluid level should be checked with the engine run- 61. ning and the brake pedal applied. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither A nor B (F.6)
D
The brake pedal is low and spongy; all brake adjustments have been completed according to specifications. The cause of the problem could be: A. Binding pedal linkage. B. Dented brake line. C. Plugged compensating port. D. A weak hydraulic hose.
D
To test the brake warning light circuit: A. Drain the master cylinder, start the engine, and watch for the warning light to illuminate. B. Disconnect the switch, start the engine, and apply moderate brake pressure. C. Replace the switch because it may be faulty. D. Ground the warning switch wire with the ignition on. (A.3.4)
D
When discussing the brake rotor measurement in the figure above, Technician A says the brake rotor is being measured for run out. Technician B says this measure- ment should be made at three locations around the rotor. Who is right? A. Aonly B. Bonly C. Both A and B D. Neither A nor B
D
When pressure testing a hydraulic brake system equipped with a metering valve and proportioning valves: A. During moderate brake application, the pressure at the master cylinder should exceed the pressure at the front wheel calipers. B. Below the split point pressure, the pressure at the master cylinder should exceed the pressure at the rear wheel cylinders. C. During a moderate brake application, the pressure should be equal at the front and rear wheels. D. Above the split point pressure, the p
D
When removing the master cylinder, all of the following steps must be performed EXCEPT: A. Relieve any vacuum boost pressure (if equipped with power brakes). B. Plug the ends of the brake lines to prevent fluid loss. C. Disconnect the float level sensor. D. Drain the master cylinder.
D
While discussing a load-sensing proportioning valve, Technician A says this valve reduces brake pressure to the rear wheels as the rear suspension load increases. Technician Bsays this valve has linkage connected from the valve to the rear chas- sis. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither Anor B
D
While discussing brake hose replacement, Technician A says the sealing washer on the male end of a brake hose shown in the illustration may be reused. Technician B says the brake line fitting should be installed and tightened in the female end of the brake hose before the male end is installed. Who is right? A. Aonly B. Bonly C. BothAandB D. N e i t h e r A n o r B
D
While road testing a vehicle with ABS, a clicking noise is heard for a short time when the engine is started and the vehicle starts off at low speed. During a normal stop when the ABS function is not operating, pedal pulsations are experienced. Technician Asays the clicking noise may be caused by defective solenoids in the ABS hydraulic control unit. Technician Bsays the pedal pulsations are normal on an ABS system. Who is right? A. Aonly B. Bonly C. Both Aand B D. Neither Anor B
D
36. During a final road test, all of the following will cause a pull while braking EXCEPT: A. mismatched tire pressure. B. contaminated brake linings. C. draggingparkingbrakes. D. a seized caliper piston.
Dragging parking brakes will not cause the vehicle to pull unless the rear brakes are unevenly adjusted. This is a function of drum brake adjustment, not parking brake adjustment. Also rear wheels or brakes seldom will cause a vehicle to pull to one side. The other answers would. T h e correct answer is C.
31. All of the following lubricants may be used when reassembling a brake caliper EXCEPT: A. silicone grease. B. rubber grease. C. the right brake fluid for the system. D. lithium grease.
Lithium grease is only used to lubricate mechanical interference points. It is not recommended for rebuilding a brake caliper. The other greases listed in the questions may be appropriate; always fol- low the recommendations of the manufacturer. T h e correct a n s w e r is D.
67. Adiagnostic trouble code (DTC) representing the L/R wheel speed sensor is obtained in the ABS. This DTC may be caused by: A. an open circuit at R/R wheel signal low connected to the ABS module. B. a grounded circuit on the L/R wheel signal low connected to the ABS module. C. a larger tire than specified by the manufacturer on the L/R wheel. D. an open circuit in the electronic brake control. (F.4)
Mismatched tire sizes will not cause brake drag. This will cause other problems, but not drag; therefore answer choice B is wrong. The other answer choices are correct and t h e c o r r e c t answer is B
15. When flushing a hydraulic system, Technician Asays each bleeder screw is opened until all of the contaminated fluid is removed. Technician B says the fluid may be reused fi it appears to be clean. Who is right? A. Aonly B. Bonly C. BothAandB D. Neither A nor B
Only Technician A is right. Technician B is wrong. Brake fluid should never be reused. T h e cor- rect answer is A.
68. An ABS-equipped rear-wheel-drive vehicle experiences lockup on both rear wheels during the anti-lock brake mode. Technician A says larger than specified tires may be installed o n the rear wheels. Technician B says the rear tires may not be the same size on each rear wheel. Who is right? A. A o n l y B. Bonly C. BothAandB D. N e i t h e r A n o r B
Reduced stopping ability can be caused by mechanical brake problems such as an improper brake adjustment; incorrect, glazed, or oil soaked linings; seized wheel cylinder pistons; or bell-mouthed, barrel-shaped or scored brake drums. Technician A is wrong; the problem may be the brake shoes and probably not the tires. Technician B is right. The correct a n s w e r is B.
5. While discussing master cylinder removal o n a vehicle equipped with manual brakes, Technician A says there is no procedural difference between manual brakes and power brakes other than the brake booster. Technician B says the push rod must be disconnected from the brake pedal unlike a power brake system. Who is right? A. A only B. B o n l y C. BothAandB D. Neither Anor B
Technician A is wrong; in some vehicles that have power brake system master cylinders, the vac- u m valve from the booster must be removed and the pressure warning switch connector discon- nected before lifting off the master cylinder.Technician B is right. In vehicles that have manual brake system master cylinders, the pushrod must be disconnected from the brake pedal before the master cylinder can be removed. The correct answer is B.
27. A restricted disc brake caliper hose could result in all of the following EXCEPT: A. dragging brakes. B. the vehicle will pull to that side under heavy braking. C. brake pedal pulsation. D. poor stopping.
The correct answer is C. A restricted disc brake caliper hose would not cause pedal pulsation. Pulsation is caused by something being loose or by an unparallel rotor. The other answer are true statements.
29. Evidence of brake fluid around the caliper boot area indicates: A. an over-filled master cylinder. B. a bad caliper seal. C. restricted brake lines. D. worn caliper pins and bushings.
The only answer that would cause a fluid residue around the caliper bore area is choice B, a bad caliper seal. An over-filled master cylinder would leak fluid at the reservoir. A restricted brake line would not cause a fluid leak nor would worn caliper pins and bushings. The correct answer is B.
16. When pressure testing a power assist brake system with the engine running, the pedal should: A. be firm 0.5 in (12.7 m m ) above the specified height. B. slowly sink after initial fi r m application. C. be firm at the specified pedal height. D. be firm 0.5 in (12.7 mm) below the specified pedal height. (D.1)
When pressure testing a power assist brake system with the engine running, the pedal should be firm and at the specified height. The correct answer is C.
38. With the engine idling, the vacuum from the intake manifold to the brake booster is found to be below specification. The technician should then: A. Connect the vacuum gauge directly to the intake manifold. B. Conclude that the brake booster is faulty and rebuild it. C. Check the brake fluid level. D. Increase the engine rpm and recheck the vacuum. (D.3)
With the engine idling, if the vacuum from the intake manifold to the brake booster is found to be low, vacuum at the manifold should be measured before further testing and before replacing any parts. The correct answer is A.
