ASE A5 Practice Test Brakes

A vehicle with power assisted brakes has a hard brake pedal. Which of the following is LEAST likely to cause this condition? A. Master cylinder. B. Vacuum check valve. C. Brake booster. D. Low manifold vacuum.

Answer A is correct. Faulty master cylinders do not typically result in a hard brake pedal. Actually it's more common for a faulty master cylinder to cause a low brake pedal that fades to the floor as it is applied. This is the least likely component listed to result in a hard brake pedal.

The left front brake of a four wheel disc brake system is dragging. Which of these is LEAST likely to cause this condition? A. Glazed brake pads. B. Restriction in the brake line. C. Rusted caliper slides. D. Twist in the brake hose.

Answer A is correct. Glazed brake pads result from excessive heat. This heat can be caused by a dragging brake unit. Glazing is more a problem with drum brake systems than disc systems because pads get more ventilation. Glazed shoes or pads cause brake fade resulting in a loss of friction and reduced braking performance.

The brakes of a four wheel disc brake system are self-applying and locking up after only a few miles of travel. Which of the following is MOST likely the cause of this condition? A. A blocked master cylinder replenishing port. B. A blocked master cylinder vent port. C. Worn master cylinder cup seals. D. Low intake manifold vacuum.

Answer B is correct. Blocking the vent port can lead to pressure buildup and brake lockup. The vent or compensation port allows for the expansion of brake fluid. Brake fluid expands as brake fluid temperature rises from normal braking. If the port is blocked, excessive pressure will cause the brake units to self-apply.

During a test drive the technician notices an excessive vibration in the steering wheel only when the brakes are applied. The front brake rotors have just been replaced for this same vibration. Which of these is MOST likely the cause of this condition. A. Excessive lateral runout. B. Rusty hub flange. C. This is a normal condition. D. Excessive thickness variation.

Answer B is correct. Debris, rust, or a bent hub flange will result in excessive front end vibration while brak

The front brakes of a vehicle with a front disc rear drum brake system skid when the brakes are first applied. Which of these is causing this skid condition? A. Proportioning valve. B. Metering valve. C. Pressure differential switch. D. Contaminated brake fluid.

Answer B is correct. The metering valve delays hydraulic pressure to the front brakes and gives the system a chance to overcome rear drum spring tension. The metering valve helps achieve balanced braking.

The red brake warning light on the instrument panel illuminates only when the brakes are applied. Which of these will result in this condition. A. A burned brake light bulb. B. Air in the hydraulic brake system. C. A damaged wheel speed sensor tone ring. D. An open in the brake switch circuit.

Answer B is correct. The red brake warning light will illuminate if there's a loss in pressure in one of the two hydraulic brake circuits, if the parking brake is engaged, or if the key is in the ON/RUN position.

The amber ABS fault light is illuminated on a vehicle's instrument panel. The vehicle contains a four channel permanent magnet sensor ABS brake system. All of these are true EXCEPT. A. Oversized tires will have an adverse effect on this ABS system. B. The gap between the sensor and the tone ring is critical with PM sensor operation. C. Permanent magnet sensor systems function well at speeds below 5 mph. D. Permanent magnet sensors and companion tone rings produce a AC frequency converted to DC pulses by the ABS controller.

Answer C is correct. A These systems typically remain passive at lower speeds. ABS systems remain passive and are activated when a possible skid is detected, this is not likely at 5mph.

A vehicle has a low spongy brake pedal. Which of these is LEAST likely to result in this condition? A. Loose wheel bearings. B. Contaminated brake fluid. C. Worn brake pads. D. Air in the hydraulic system.

Answer C is correct. Low brake pads would result in a warning clip squeal or tire pad sensor light illumination.

The left front inner most pad on a four wheel disk brake system is excessively worn. The outside pad has little wear. Which if these has caused this uneven pad wear. A. Proportioning valve. B. Metering valve. C. Brake caliper slide pins. D. Uneven rotor thickness.

Answer C is correct. Sticking brake caliper slide pins result in inboard pad wear. This is because the floating or outside brake pad/unit is unable to apply its clamping force on the rotor.

The rear wheels of a vehicle are locking up only when the brakes are applied. This is caused by a faulty: A. Metering valve. B. Pressure differential switch. C. Proportioning valve. D. Brake switch.

Answer C is correct. The proportioning valve prevents rear wheel lockup.

A three-function combination valve has all of these EXCEPT a: A. Proportioning valve. B. Metering valve. C. Solenoid valve. D. Brake failure light switch.

Answer C is correct. The solenoid valve is not part of the combination valve.

A vehicle pulls to the left only when the brakes are applied. This condition is MOST likely caused by: A. A seized left front caliper. B. A restriction in the left front brake line. C. Leaking master cylinder cup seals. D. A seized right front caliper.

Answer D is correct. A frozen right front caliper will cause the vehicle to pull to the left when braking.

A vehicle's right front wheel has a growl that increases with vehicle speed. The MOST likely cause is: A. Excessive rotor lateral run out. B. Warped rear brake drums. C. Worn CV-Joint. D. Worn wheel bearing.

Answer D is correct. A worn wheel bearing will cause a growl that increases with vehicle speed.

The red brake warning light is illuminated on the instrument panel of a vehicle with four wheel disc brakes. Which of these is LEAST likely to cause this warning light to illuminate. A. Low brake fluid level. B. Unequal brake fluid pressure. C. Grounded parking brake circuit. D. Loose wheel speed sensor plug.

Answer D is correct. Answer D is correct because this is the only answer that would illuminate the amber warning light instead of the red brake warning light.

The right brake light is inoperative when the brake pedal is depressed. All the other lights function properly. Which of the following should be inspected when diagnosing this inoperative brake light circuit? A. The right rear bulb socket. B. The right rear bulb. C. The brake light fuse. D. Both A and B

Answer D is correct. Both A and B are correct. Check the socket and the bulb for operation and resistance.

Which of the following brake fluids are silicone based. A. Dot 2 B. Dot 3 C. Dot 4 D. Dot 5

Answer D is correct. Dot 5 brake fluid is silicon based.

A vehicle stops but the brake pedal fades completely to the floorboard afterwards. There are no external leaks. Which of these is the MOST likely cause of this condition. A. Faulty vacuum brake booster. B. Clogged vacuum booster check valve. C. Dark discolored brake fluid. D. Master cylinder cup seals.

Answer D is correct. Master cylinder cup seals wear and create an internal leak. The pedal fades to the floor as fluid bypasses the seal.

A technician is measuring the inside diameter of a brake drum with a brake drum micrometer. The technician should use which of the following measurements A. The smallest measurement. B. A brake drum tool is not used. C. The average of all the measurements. D. The largest measurement.

Answer D is correct. The largest measurement is used.

Which of these is not part of an integral ABS unit. A. Hydraulic Booster B. Master Cylinder C. Hydraulic Modulator D. Vacuum Booster

Answer D is correct. The vacuum booster is not part of in integrated or integral ABS system.

A vehicle has a low brake pedal. Technician A says an improperly adjusted brake pedal could be the cause. Technician B says overheated brake fluid could cause this condition. Who is correct?

Both Technicians are correct. An under adjusted brake pedal will cause a low brake pedal. Excessive heat damages brake fluid resulting in a spongy or low brake pedal.

The front brake pads on a vehicle with a quick take up master cylinder need replacement. They were replaced just recently. Technician A says this is a low drag brake system. Technician B says this could be caused by a sticking quick take up valve. Who is correct?

Both technicians are correct

A vehicle suffers from uneven pad wear. Technician A says to check for sticking slide pins. Technician B says this could be caused by a sticking caliper piston. Who is correct?

Both technicians are correct.

A vibration is felt in the steering wheel only while braking. Technician A says excessive lateral runout on the front rotors will result in this condition. Technician B says to use a dial indicator to check lateral runout. Who is correct?

Both technicians are correct.

An integral drum parking brake system is being discussed. Technician A says a binding cable will prevent parking brake application. Technician B says this system contains a brake strut. Who is correct?

Both technicians are correct.

Technician A says ABS control units are programmed to ignore speed sensor input variations below a certain threshold. Technician B says a one-channel ABS system controls hydraulic pressure to the rear brake units. Who is correct?

Both technicians are correct.

Technician A says PM passive permanent magnet ABS wheel speed sensors produce AC voltage. Technician B says input from wheel speed sensors are used for anti-lock brake, electronic traction control, and electronic stability control systems. Who is correct?

Both technicians are correct.

Technician A says electronic stability control systems require four wheel speed sensors. Technician B says the telltale lamp will flash when the ESC system is activated. Who is correct?

Both technicians are correct.

Two technicians are inspecting a brake drum for wear. Technician A says if the brake drum has small cracks along it's inside lining it should be replaced. Technician B says if a brake drum has minor pitting along it's inside lining it may be resurfaced. Who is correct?

Both technicians are correct.

Technician A says an outside micrometer is the preferred tool for measuring rotor lateral runout. Technician B says a dial indicator is the preferred tool used for measuring rotor thickness. Who is correct?

Neither Technician A or B is correct. A micrometer is used for measuring rotor thickness. A dial indicator is used to measure lateral runout.

Technician A says double flare copper tubing is used for brake lines. Technician B says single flare steel tubing is used for brake lines. Who is correct?

Neither technician is correct.

Technician A says to use the original brass washer when installing a new flexible brake hose. Technician B says to use a compression fitting to repair a small leak in a stainless steel brake line. Who is correct?

Neither technician is correct.

The brake shoes on the rear of a vehicle are worn and must be replaced. Technician A says the primary shoe faces the front of the vehicle. Technician B says the lining of the primary shoe must be riveted to the shoe plate. Who is correct?

TECH A is correct. Also the primary shoe usually has a shorter lining than the secondary.

A vehicle with a vacuum brake booster has a hard pedal with little stopping power. Technician A says a kink in the check valve's hose will result in this condition. Technician B says a vacuum booster needs at least 12 Hg of vacuum to operate properly. Who is correct?

TECH A is correct. An inoperative brake booster, a faulty check valve or a kink in its hose will result in a hard brake pedal.

A hydro-boost brake system has reduced braking performance. Technician A says to check the power steering system. Technician B says to check the vacuum check valve. Who is correct?

TECH A is correct. The power steering pump produces pressure for the Hydro-Boost unit.

Two technicians are discussing brake backing plates. Technician A says if a ridge has formed on the pads where the shoes rest they may be filed to restore a smooth finish. Technician B says to apply bearing grease to reduce brake squeak. Who is correct?

TECH A is correct. The ridge often formed by the movement of the brake shoe may be filed smooth.

A technician is lubricating rubber brake components while performing a brake job. Technician A says to use a high temperature silicon based lubricant. Technician B says to use a good petroleum based lubricant. Who is correct?

TECH A is correct. Use high temperature silicon based lubricant that does not contain petroleum.

Technician A says to adjust a height sensing proportioning valve while on the lift. Technician B says to adjust a height sensing proportioning valve at vehicle curb ride height. Who is correct?

TECH B is correct. Adjust a height sensing proportioning valve at curb height with all four tires firm on the ground. Adjusting this type of proportioning valve on a lift would reduce rear brake performance.

Technician A says accumulators are found only on non-integral ABS systems. Technician B says some integral ABS units contain high pressure accumulators that must be discharged before repair. Who is correct?

TECH B is correct. High pressure units can be dangerous and must be discharged before removal. Always check with manufacturer's procedures before disassembling an ABS unit

A vehicle's brake lights are completely inoperative. Technician A says the brake light switch may be stuck closed. Technician B says the circuit may have shorted and blown a fuse. Who is correct?

TECH B is correct. If both brake lights are out, start troubleshooting with a quick check of the circuits fuse.

Two technicians are discussing traction control systems. Technician A says if the amber TCS light flashes while driving in poor weather conditions, there is an electrical fault in the system. Technician B says these systems require an electric pump and accumulator. Who is correct?

TECH B is correct. TCS systems use an electric pump and accumulator to apply the brake on the wheel that's lost its traction.

A vehicle with ABS anti-lock brakes has an audible clicking noise when it is first started. The noise goes away after a few seconds. Technician A says this is one of the hydraulic valves in the hydraulic valve assembly sticking. Technician B says this is a normal condition. Who is correct?

TECH B is correct. The ABS system runs a system check when the key is first turned to the ON position. The valves sometimes make a clicking noise during this check.

After installation of brake pads, the pad manufacturer recommends performing a burnishing procedure. Technician A says this is accomplished by repeating several high speed stops. Technician B says this process includes light application of the brake pedal and a brief cool down period between stops. Who is correct?

TECH B is correct. The burnishing or break in procedure cures the friction materials in the pads. It provides for better braking performance.

The brake pad wear indicator light is illuminated on the instrument panel. Technician A says this is because the brake pads have become contaminated. Technician B says this is the pad wear sensor contacting the brake rotor. Who is correct?

TECH B is correct. When the sensors tip contacts the rotor, the pad warning light illuminates on the instrument panel.

Two technicians are discussing master cylinder residual check valves. Technician A says the check valve is used on four wheel disc brake systems. Technician B says the valve maintains pressure when the brakes are released. Who is correct?

Technician B is correct. The constant low pressure, usually 6 psi to 8 psi keeps air from entering the wheel cylinders.