T4 ASE BRAKES (MEDIUM/HEAVY
DUTY BRAKES) EXAM QUESTIONS
AND ANSWERS WITH CORRECT
SOLUTIONS
1) The brake pedal feels soft after the master cylinder has been replaced.
Technician A says that a leaking power booster could be the cause.
Technician B says that air in the hydraulic system could be the cause.
Who is right? - ANSWER - B only
Explanation: A leaking power brake booster will cause the brake pedal to be hard. Technician A's
statement is false. Air in the hydraulic system may cause the pedal to be soft. Technician B's statement
is true. The correct answer is B.
2) A vehicle's brake pedal goes to the floor.
Technician A says that an internal master cylinder leak could be the cause.
Technician B says that seized wheel cylinder pistons could be the cause.
Who is right? - ANSWER - A only
Explanation: Fluid bypassing the master cylinder primary cup may cause the brake pedal to go to the
floor. Technician A's statement is true. Seized wheel cylinder pistons will not cause the brake pedal to go
to the floor. Technician B's statement is false. The correct answer is A.
3) A vehicle pulls to the left during braking and pulls right without braking. This could be caused by: -
ANSWER - a collapsed right front brake hose.
Explanation: Unequal tire pressure will cause a pull to one side with or without braking. A failed master
cylinder will not cause a pull. A seized left front caliper will cause a pull to the right during braking. A
, collapsed right front brake hose may trap pressurized fluid between the hose and the caliper piston
causing a pull to the right without brake application. The collapsed hose may restrict fluid flow to the
caliper piston when the brakes are applied, causing a pull to the left. The correct answer is C.
4) The front of the vehicle dips noticeably during braking on a vehicle with disc/drum brakes. Which of
these could be the cause? - ANSWER - Stuck-open metering valve
Explanation: The proportioning valve moderates pressure to the rear wheels. A collapsed front brake
hose or seized caliper pistons will not cause the symptom. A stuck-open metering valve will allow the
front brakes to apply too soon causing the front of the vehicle to dip. The correct answer is B.
5) Technician A says that the bleeder valve on the caliper should be opened when collapsing a caliper
piston.Technician B says that the brake hose should be clamped when collapsing a caliper piston.Who is
right? - ANSWER - A only
Explanation: The purpose of opening the bleeder is to prevent contaminated fluid in the caliper from
being pushed back into the hydraulic system. Technician A's statement is true. The brake hose should
never be clamped as this may cause damage to the hose. Technician B's statement is false. The correct
answer is A.
6) Technician A says that DOT 5 brake fluid can be substituted where DOT 3 brake fluid is
specified.Technician B says that a scan tool may be required to bleed the brakes on some vehicles.Who
is right? - ANSWER - B only
Explanation: DOT 5 brake fluid is not compatible with DOT 3 brake fluid. Technician A's statement is
false. Some vehicles with ABS or TCS may require a scan tool to activate the system to properly bleed
brakes. Technician B's statement is true. The correct answer is B.
7) A vehicle has a low brake pedal. Which of these could be the cause? - ANSWER - A seized star adjuster
DUTY BRAKES) EXAM QUESTIONS
AND ANSWERS WITH CORRECT
SOLUTIONS
1) The brake pedal feels soft after the master cylinder has been replaced.
Technician A says that a leaking power booster could be the cause.
Technician B says that air in the hydraulic system could be the cause.
Who is right? - ANSWER - B only
Explanation: A leaking power brake booster will cause the brake pedal to be hard. Technician A's
statement is false. Air in the hydraulic system may cause the pedal to be soft. Technician B's statement
is true. The correct answer is B.
2) A vehicle's brake pedal goes to the floor.
Technician A says that an internal master cylinder leak could be the cause.
Technician B says that seized wheel cylinder pistons could be the cause.
Who is right? - ANSWER - A only
Explanation: Fluid bypassing the master cylinder primary cup may cause the brake pedal to go to the
floor. Technician A's statement is true. Seized wheel cylinder pistons will not cause the brake pedal to go
to the floor. Technician B's statement is false. The correct answer is A.
3) A vehicle pulls to the left during braking and pulls right without braking. This could be caused by: -
ANSWER - a collapsed right front brake hose.
Explanation: Unequal tire pressure will cause a pull to one side with or without braking. A failed master
cylinder will not cause a pull. A seized left front caliper will cause a pull to the right during braking. A
, collapsed right front brake hose may trap pressurized fluid between the hose and the caliper piston
causing a pull to the right without brake application. The collapsed hose may restrict fluid flow to the
caliper piston when the brakes are applied, causing a pull to the left. The correct answer is C.
4) The front of the vehicle dips noticeably during braking on a vehicle with disc/drum brakes. Which of
these could be the cause? - ANSWER - Stuck-open metering valve
Explanation: The proportioning valve moderates pressure to the rear wheels. A collapsed front brake
hose or seized caliper pistons will not cause the symptom. A stuck-open metering valve will allow the
front brakes to apply too soon causing the front of the vehicle to dip. The correct answer is B.
5) Technician A says that the bleeder valve on the caliper should be opened when collapsing a caliper
piston.Technician B says that the brake hose should be clamped when collapsing a caliper piston.Who is
right? - ANSWER - A only
Explanation: The purpose of opening the bleeder is to prevent contaminated fluid in the caliper from
being pushed back into the hydraulic system. Technician A's statement is true. The brake hose should
never be clamped as this may cause damage to the hose. Technician B's statement is false. The correct
answer is A.
6) Technician A says that DOT 5 brake fluid can be substituted where DOT 3 brake fluid is
specified.Technician B says that a scan tool may be required to bleed the brakes on some vehicles.Who
is right? - ANSWER - B only
Explanation: DOT 5 brake fluid is not compatible with DOT 3 brake fluid. Technician A's statement is
false. Some vehicles with ABS or TCS may require a scan tool to activate the system to properly bleed
brakes. Technician B's statement is true. The correct answer is B.
7) A vehicle has a low brake pedal. Which of these could be the cause? - ANSWER - A seized star adjuster
