AUTOMOTIVE SERVICE EXCELLENCE (ASE) A5 CERTIFICATION
PRACTICE EXAMINATION (2025/2026 EDITION) BRAKES
SYSTEMS – FUNDAMENTALS, DIAGNOSIS, INSPECTION,
SERVICE PROCEDURES, AND PERFORMANCE TESTING
|MASTER LEVEL REVIEW FOR AUTOMOTIVE BRAKE SYSTEMS
TECHNOLOGY
hydraulic brake systems | disc & drum brakes | abs (anti-lock braking system) |
electronic brake control systems | parking brakes | brake fluid service | bleeding
procedures | fault diagnosis & troubleshooting | safety inspection standards |
OEM service specifications
On a car with disc/drum brakes, the front brakes grab quickly when light pedal pressure is
applied. This problem could be caused by a bad:
A. Proportioning valve
B. Pressure safety switch
C. Metering valve
D. Residual check valve
The correct answer is C. The metering valve delays the flow of brake fluid to the front calipers
until the pressure in the system rises to a point where the wheel cylinder can overcome the
tension of the brake shoe returning spring. The purpose is to have both front and rear brakes
apply simultaneously. This prevents the front brakes from locking up during light brake
applications.
The driver of a vehicle with power disc/drum brakes says that the brake pedal moved slowly to
the floor while maintaining pedal pressure at a stoplight. What could cause this problem?
A. Leaking primary piston cup in master cylinder
1|Page
,B. Leaking power brake booster
C. Leaking residual check valve in master cylinder
D. Internal leak in the combination valve
The correct answer is A. if the primary piston cup in the master cylinder is leaking, pressure will
not build up ahead of the primary piston to increase pressure to the rear brakes. The piston will
then move forward until the spring is compressed enough to move the secondary piston.
Consequently, this internal leak will cause the brake pedal to slowly drop to the floor.
What is the purpose of the master cylinder residual check valve(s) on vehicles equipped with
drum brakes?
A. Allowed the driver to pump up the brakes
B. Prevents air from entering the hydraulic system
C. Prevents wheel lockup by reducing the hydraulic pressure
D. Reduces pedal pulsation by controlling hydraulic pressure
The correct answer is B. Residual check valve(s) are used on drum brakes to keep residual low
pressure (slight static pressure) in the brake system at all times even when the brake pedal is
released. This pressure (5-20 psi) keeps the lips of the wheel cylinder piston cups tight against
the cylinder walls to prevent air from entering the system when at rest (brakes released).
A technician has just overhauled the front brakes on a vehicle with front disc and rear drum
brakes. However, when he attaches a pressure bleeder (pressurized to about 25 psi) to the
master cylinder, he cannot get any fluid to come out of the disc brake caliper bleeder screws.
Which of the following is MOST LIKELY the cause?
A. Bad proportioning valve
B. Bad pressure differential valve
C. proportioning valve release button not activated
D. Metering valve release button not activated
2|Page
,The correct answer is D. A metering valve requires a minimum pressure (typically 75-125 psi) to
open. At this point pressurized fluid flows to the front calipers. Since the bleeder tank is only
pressurized to 25 psi, fluid pressure is too low to open the metering valve during this procedure,
Therefore, when you use a pressure bleeder on a system with a metering valve, you must
manually keep the valve open by either pushing the button in the end of the valve, or pulling
the stem outward on the end of the valve.
On a vehicle with single piston floating caliper front disc brakes, the brake pads on the left side
of the vehicle are almost completely worn while the right side is almost new. Tech A says that
too much rotor runout could be the cause. Tech B says that a binding caliper piston could be the
cause. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B
The correct answer is B. Excessive rotor runout would cause a pulsating brake pedal, but not
uneven side-to-side pad wear. A frozen caliper piston on the other hand, will keep both inner
and outer brake pads equally applied against the rotor even when the brake pedal is released.
This constant friction will cause rapid pad wear in the affected caliper as well as the front-end
pull
A hydraulic brake line is leaking. Which of the following is the correct repair procedure?
A. Cut out the bad section and replace with new steel tubing using compression fittings.
B. Replace the leaking line with double-flared, seamless copper tubing.
C. Cut out the bad section and replaced with single-flared steel tubing using flare nuts and
unions.
D. Replace the leaking line with double-flared steel tubing.
3|Page
, The correct answer is D. Steel tubing of the same size, type, and length with double flared ends
must be used when replacing a traditional SAE double inverted flair style hydraulic brake line.
Which of the following problems would be caused by using a residual check valve in a disc brake
master cylinder?
A. Reduced brake pedal travel
B. Reduced brake system pressure
C. Increased brake pad wear
D. Increased rotor runout.
The correct answer is C. If a residual check valve was installed in a disc brake master cylinder, it
would cause increased brake pad wear since the residual brake pressure would cause the caliper
pistons to keep the pads applied even when the brake pedal is released.
A customer complains that their vehicle pulls to the right when the brakes are applied.
Technician A says a restricted brake line to the left caliper can cause this problem. Technician B
says a malfunctioning proportioning valve is probably the cause. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B
The correct answer is A. A restriction in the brake line will cause a drop in fluid pressure to the
affected caliper. This will cause the caliper to be unable to exert the same force against the pads
as the unrestricted side. because of this, the vehicle will pull to the side where the pressure is
highest and brake force is greatest. In this case, that would be the right side.
4|Page
PRACTICE EXAMINATION (2025/2026 EDITION) BRAKES
SYSTEMS – FUNDAMENTALS, DIAGNOSIS, INSPECTION,
SERVICE PROCEDURES, AND PERFORMANCE TESTING
|MASTER LEVEL REVIEW FOR AUTOMOTIVE BRAKE SYSTEMS
TECHNOLOGY
hydraulic brake systems | disc & drum brakes | abs (anti-lock braking system) |
electronic brake control systems | parking brakes | brake fluid service | bleeding
procedures | fault diagnosis & troubleshooting | safety inspection standards |
OEM service specifications
On a car with disc/drum brakes, the front brakes grab quickly when light pedal pressure is
applied. This problem could be caused by a bad:
A. Proportioning valve
B. Pressure safety switch
C. Metering valve
D. Residual check valve
The correct answer is C. The metering valve delays the flow of brake fluid to the front calipers
until the pressure in the system rises to a point where the wheel cylinder can overcome the
tension of the brake shoe returning spring. The purpose is to have both front and rear brakes
apply simultaneously. This prevents the front brakes from locking up during light brake
applications.
The driver of a vehicle with power disc/drum brakes says that the brake pedal moved slowly to
the floor while maintaining pedal pressure at a stoplight. What could cause this problem?
A. Leaking primary piston cup in master cylinder
1|Page
,B. Leaking power brake booster
C. Leaking residual check valve in master cylinder
D. Internal leak in the combination valve
The correct answer is A. if the primary piston cup in the master cylinder is leaking, pressure will
not build up ahead of the primary piston to increase pressure to the rear brakes. The piston will
then move forward until the spring is compressed enough to move the secondary piston.
Consequently, this internal leak will cause the brake pedal to slowly drop to the floor.
What is the purpose of the master cylinder residual check valve(s) on vehicles equipped with
drum brakes?
A. Allowed the driver to pump up the brakes
B. Prevents air from entering the hydraulic system
C. Prevents wheel lockup by reducing the hydraulic pressure
D. Reduces pedal pulsation by controlling hydraulic pressure
The correct answer is B. Residual check valve(s) are used on drum brakes to keep residual low
pressure (slight static pressure) in the brake system at all times even when the brake pedal is
released. This pressure (5-20 psi) keeps the lips of the wheel cylinder piston cups tight against
the cylinder walls to prevent air from entering the system when at rest (brakes released).
A technician has just overhauled the front brakes on a vehicle with front disc and rear drum
brakes. However, when he attaches a pressure bleeder (pressurized to about 25 psi) to the
master cylinder, he cannot get any fluid to come out of the disc brake caliper bleeder screws.
Which of the following is MOST LIKELY the cause?
A. Bad proportioning valve
B. Bad pressure differential valve
C. proportioning valve release button not activated
D. Metering valve release button not activated
2|Page
,The correct answer is D. A metering valve requires a minimum pressure (typically 75-125 psi) to
open. At this point pressurized fluid flows to the front calipers. Since the bleeder tank is only
pressurized to 25 psi, fluid pressure is too low to open the metering valve during this procedure,
Therefore, when you use a pressure bleeder on a system with a metering valve, you must
manually keep the valve open by either pushing the button in the end of the valve, or pulling
the stem outward on the end of the valve.
On a vehicle with single piston floating caliper front disc brakes, the brake pads on the left side
of the vehicle are almost completely worn while the right side is almost new. Tech A says that
too much rotor runout could be the cause. Tech B says that a binding caliper piston could be the
cause. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B
The correct answer is B. Excessive rotor runout would cause a pulsating brake pedal, but not
uneven side-to-side pad wear. A frozen caliper piston on the other hand, will keep both inner
and outer brake pads equally applied against the rotor even when the brake pedal is released.
This constant friction will cause rapid pad wear in the affected caliper as well as the front-end
pull
A hydraulic brake line is leaking. Which of the following is the correct repair procedure?
A. Cut out the bad section and replace with new steel tubing using compression fittings.
B. Replace the leaking line with double-flared, seamless copper tubing.
C. Cut out the bad section and replaced with single-flared steel tubing using flare nuts and
unions.
D. Replace the leaking line with double-flared steel tubing.
3|Page
, The correct answer is D. Steel tubing of the same size, type, and length with double flared ends
must be used when replacing a traditional SAE double inverted flair style hydraulic brake line.
Which of the following problems would be caused by using a residual check valve in a disc brake
master cylinder?
A. Reduced brake pedal travel
B. Reduced brake system pressure
C. Increased brake pad wear
D. Increased rotor runout.
The correct answer is C. If a residual check valve was installed in a disc brake master cylinder, it
would cause increased brake pad wear since the residual brake pressure would cause the caliper
pistons to keep the pads applied even when the brake pedal is released.
A customer complains that their vehicle pulls to the right when the brakes are applied.
Technician A says a restricted brake line to the left caliper can cause this problem. Technician B
says a malfunctioning proportioning valve is probably the cause. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B
The correct answer is A. A restriction in the brake line will cause a drop in fluid pressure to the
affected caliper. This will cause the caliper to be unable to exert the same force against the pads
as the unrestricted side. because of this, the vehicle will pull to the side where the pressure is
highest and brake force is greatest. In this case, that would be the right side.
4|Page
