2026/2027/2028 Testing Cycle
55 Questions & Answers | Verified Rationales
Guaranteed Pass | Graded A+
,Q1: A customer complains that the brake pedal slowly sinks to the floor while holding steady
pressure at a red light. No external fluid leaks are visible anywhere on the vehicle. Technician A
says the master cylinder primary cup seal is leaking internally. Technician B says a faulty power
brake booster check valve is the cause. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: A
Rationale: A pedal that slowly sinks under constant pressure with no external leaks is the classic
symptom of an internal leak in the master cylinder, where fluid bypasses the primary cup seal. A
faulty booster check valve would cause a hard pedal or rough idle, not a sinking pedal.
Q2: A technician is testing a vacuum power brake booster. The correct procedure is to pump the
brake pedal at least four times with the engine off, hold the pedal depressed, and then start the
engine. What should the technician observe?
A. The pedal should remain firm and not move
B. The pedal should drop slightly and then remain firm
C. The pedal should rise and become hard
D. The pedal should sink slowly to the floor
Answer: B
Rationale: When the engine starts, vacuum is restored to the booster, and the pedal should drop
slightly as the booster assists the braking force, then remain firm. A pedal that does not drop
indicates a faulty booster or check valve.
Q3: A technician is checking a brake rotor for variations in thickness (parallelism). Which tool
should be used to perform this measurement?
A. Dial indicator
B. Micrometer
C. Vernier caliper
D. Feeler gauge
Answer: B
, Rationale: A micrometer is used to measure rotor thickness and parallelism (thickness variation).
A dial indicator is used to measure lateral runout (wobble), not thickness.
Q4: A vehicle has a hard brake pedal and a rough engine idle that worsens when the brake pedal
is pressed. Technician A says the vacuum brake booster diaphragm is torn. Technician B says the
booster check valve is stuck closed. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: A
Rationale: A torn or cracked internal vacuum diaphragm causes a vacuum leak, resulting in a
hard brake pedal and a rough engine idle (because unmetered air enters the intake manifold). A
stuck-closed check valve would cause a hard pedal but not a rough idle.
Q5: A driver complains that the brake pedal is spongy and requires pumping to stop effectively.
Technician A says air is trapped in the hydraulic system. Technician B says the brake fluid is
contaminated with moisture. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: A
Rationale: A spongy pedal that temporarily stiffens when pumped is the classic symptom of air in
the hydraulic lines. Moisture contamination typically causes a low pedal or corrosion, not a
spongy pedal that responds to pumping.
Q6: During a brake inspection, a technician finds that the inner brake pad on the left front wheel
is worn significantly more than the outer pad. What is the most likely cause?
A. Seized caliper piston
B. Seized caliper slide pins
C. Warped rotor
D. Faulty proportioning valve