WITH CORRECT ANSWERS 2025-2026
A vehicle is equipped with a vacuum brake booster. It doesn't have power assist until the engine r
uns for a minute, then it begins to work normally. What is the most likely reason?
A. Defective check valve
B. Adjusted brake pedal push rod is too short
C. Front brake disc is worn
D. Engine requires a tune-up to produce a higher vacuum at idle speed CORRECT
ANSWER A -
The defective check valve causes a loss in vacuum when the engine is off. That's why the power a
ssist begins to function properly after the engine runs. The other three answers wouldn't cause the
same issues.
The brake pedal starts to feel spongy and low even though all the adjustments have been made ac
cording to the specifications. What could be the cause of the problem?
A. Dented brake line
B. Binding pedal linkage
C. Weak hydraulic hose
D. Plugged compensating port CORRECT ANSWER C -
The weak hydraulic brake hose causes a spongy pedal. The pressure can continue to build and the
hose might expand, but not release the pressure to the brake units. Binding pedal linkage would l
ead to a hard pedal, which is also true for a dented brake line. The plugged compensator port lea
ds to dragging brakes instead.
The lack of brake pedal free play on a vehicle might cause:
A. Spongy brake pedal
B. Low brake pedal
C. Pressure build-up and dragging brakes
D. Fluid leaking beyond the primary piston cups CORRECT ANSWER C -
when there's no free play, the brakes can't disengage fully. This leads to the brakes dragging. The
other situations wouldn't be caused by the lack of free play.
When you remove the master cylinder, you must take all these steps EXCEPT:
, A. Disconnect the float level sensor
B. Plug the ends of the brake lines to prevent fluid loss
C. Vacuum boost pressure with power brakes
D. Drain the master cylinder CORRECT ANSWER D -
Draining the master cylinder isn't required. If it needs to be done, the fluid can be removed after
the lines are capped. Fluid will not run from the master cylinder while you remove it. Then, it's ea
sier to empty once it's out.
Brakes on an older vehicle with a quick take up valve in the master cylinder are being bled. Techni
cian A believes that you must depress the quick take up valve. Technician B believes that the brake
s can't be bled. Who is correct?
A. Technician A
B. Technician B
C. Both technicians
D. Neither technician CORRECT ANSWER D -
Both of these techs are wrong. The brakes on quick take up systems use the exact bleeding proce
dure as systems without the valve. You don't need to do anything different.
A short power assist brake booster push rod will lead to which of these?
A. Illuminated brake light
B. Excessive brake pedal travel
C. Inoperative brake system
D. Excessive brake drag CORRECT ANSWER B -
The short push rod length has to travel farther to make contact. This leads to excessive pedal trav
el. The other complaints wouldn't occur as a result.
Erratic brake pulling occurs on a vehicle when the brakes are applied. All of these could cause this
problem EXCEPT:
A. Double wall steel tubing
B. Double wall copper tubing
C. Flare nuts