ASE A5 CERTIFICATION SCRIPT 2026
QUESTIONS WITH SOLUTIONS GRADED A+
◍ metering valve.
Answer: A metering valve provides balanced braking by delaying the
application of the front brakes, allowing fluid pressure to overcome rear
brake spring pressure to engage just before the fronts.Without this valve, the
front disc brakes apply almost instantly while the rear brakes still must
overcome spring pressure. The vehicle would nosedive. Nosediving is a
symptom of a faulty metering valve and may cause vehicle instability and
skid.
◍ With the brakes applied on a vehicle with power brakes, the pedal moves
down slightly when the engine is started. Technician A says the cause could
be a leaking power brake booster diaphragm. Technician B says the cause
could be a stuck closed residual check valve in the hose from the intake
manifold to the power brake booster. Who is right?.
Answer: Neither A nor BBoth technicians are wrong because this is how
power brakes are supposed to operate.
◍ DOT 5 contains BLANK.
Answer: silicon based
◍ Technician A says that DTCs can be accessed from any ABS system using
flash diagnostics. Technician B says that ABS system tests can be
performed with a bi-directional scan tool. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B.
Answer: The correct answer is B. Only a few ABS systems (primarily
, RWAL) offer flash code diagnostics for retrieving stored fault codes. A
bi-directional scan tool can be used to perform tests on ABS system
components. A technician can activate solenoids and valves while observing
the change in that circuit.
◍ When performing a vacuum booster function test, you should begin by
pumping the brake pedal several times _______________..
Answer: with the engine off
◍ During a routine vehicle maintenance, the fluid level in the master cylinder
reservoir is checked. When the reservoir cap is removed, purple colored
fluid is found in the reservoir. Technician A says that this means the fluid
should be topped off with DOT 4, which has a higher boiling point than
regular brake fluid. Technician B says that this means that the fluid is
contaminated; all rubber parts in the system must be replaced and the system
flushed. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B.
Answer: The correct answer rs D, neither technician is right. Purple is the
color of silicone fluid, and only DOT 5 fluid should be used to top off the
reservoir.
◍ The front disc brake pads are being replaced on a vehicle with composite
rotors. The left front rotor is scored below the 'machine to' but not the
'discard' thickness. The right front rotor has minor heat checks but otherwise
checks out O
K. If cast rotors are the only available replacements, which of the following
is the proper course of action?
A. Machine both rotors, being careful not to exceed the 'discard' thickness.
B. Replace the left front rotor and machine the right front.
C. Replace both rotors.
D. Replace the left front rotor and leave the right front alone..
, Answer: The correct answer is C. Composite and cast rotors should not be
mixed on the same axle. Answer A is wrong because, as the question
indicated, the rotor is already worn past the 'machine to' dimension. even if
the rotor is not machined beyond the 'discard' thickness, this leaves no
allowance for wear in the future.
◍ Technician A says that any imperfection found in a phenolic caliper piston
warrants replacement. Technician B says that a phenolic caliper piston
should be protected with a block of wood when installing it into the caliper
bore with a C-clamp. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B.
Answer: The correct answer is B. A phenolic piston should be protected to
keep it from being damaged when a C-clamp is used. Technician A is wrong
because minor surface imperfections are OK provided they do not enter the
dust boot groove area.
◍ A wheel speed sensor is being diagnosed using the OEM (original
equipment manufacturer) diagnostic scan tool. Technician A says to verify
wheel speed sensor operation, compare all four wheel speed sensor outputs
to vehicle speed on the data list. Technician B says the wheel's direction of
rotation can be verified by looking at the wheel direction on the scan tool
data list. Who is right?.
Answer: Both A and B
◍ This question has the word EXCEP
T. For this question, look for the choice that could NOT cause the described
situation. Read the entire question carefully before choosing your answer.
All of these would cause a low brake pedal, EXCEPT:.
Answer: Seized caliper pistonA seized caliper piston could cause the pedal
to be high with reduced braking power.
◍ All of the following could cause a hard brake pedal on a vehicle with power
, brakes EXCEPT:
A. An engine with the valves adjusted too tight
B. Brake fluid on the linings
C. A leak in the brake hydraulic system
D. A frozen caliper.
Answer: The correct answer is C. A leak in the hydraulic system wouldn't
cause a hard pedal but rather create the exact opposite condition due to the
hydraulic pressure loss. An engine with the valves adjusted too tight would
develop low vacuum. This would adversely affect the operation of the
power brake booster and cause a hard pedal. Brake fluid on the linings will
cause the friction material to grab resulting in a hard pedal, while a frozen
caliper would prevent retraction of the piston resulting in a similar
condition.
◍ A vehicle with 4-wheel disc brakes has a brake squeal. Technician A says a
defective proportioning valve could be the cause. Technician B says disc
brake squeal is often caused by movement of the disc brake pad during
braking. Who is right?.
Answer: B only To reduce disc brake squeal, all mating surfaces of the
brake should be clean and lubricated. Always use OEM recommended clips
and anti-squeal shims. To further reduce noise, do not machine a disc brake
rotor more than absolutely necessary. Technician A is wrong because the
proportioning valve only affects brake lockup and is not used on 4-wheel
disc brakes only on disc/drum combinations.
◍ On a car with single piston floating caliper disc brakes, the disc brake pad
between the caliper piston and the rotor is badly worn. The other brake pad
is slightly worn. Technician A says excessive rotor run out could be the
cause. Technician B says insufficient clearance between the pads and caliper
slider could be the cause. Who is right?.
Answer: Tech B only Insufficient clearance between the pads and caliper
slider causes the slider not to move and only applies one brake pad causing
only that pad to wear. Technician A is wrong because excessive rotor runout
will cause brake pulsations with no effect on wear.
QUESTIONS WITH SOLUTIONS GRADED A+
◍ metering valve.
Answer: A metering valve provides balanced braking by delaying the
application of the front brakes, allowing fluid pressure to overcome rear
brake spring pressure to engage just before the fronts.Without this valve, the
front disc brakes apply almost instantly while the rear brakes still must
overcome spring pressure. The vehicle would nosedive. Nosediving is a
symptom of a faulty metering valve and may cause vehicle instability and
skid.
◍ With the brakes applied on a vehicle with power brakes, the pedal moves
down slightly when the engine is started. Technician A says the cause could
be a leaking power brake booster diaphragm. Technician B says the cause
could be a stuck closed residual check valve in the hose from the intake
manifold to the power brake booster. Who is right?.
Answer: Neither A nor BBoth technicians are wrong because this is how
power brakes are supposed to operate.
◍ DOT 5 contains BLANK.
Answer: silicon based
◍ Technician A says that DTCs can be accessed from any ABS system using
flash diagnostics. Technician B says that ABS system tests can be
performed with a bi-directional scan tool. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B.
Answer: The correct answer is B. Only a few ABS systems (primarily
, RWAL) offer flash code diagnostics for retrieving stored fault codes. A
bi-directional scan tool can be used to perform tests on ABS system
components. A technician can activate solenoids and valves while observing
the change in that circuit.
◍ When performing a vacuum booster function test, you should begin by
pumping the brake pedal several times _______________..
Answer: with the engine off
◍ During a routine vehicle maintenance, the fluid level in the master cylinder
reservoir is checked. When the reservoir cap is removed, purple colored
fluid is found in the reservoir. Technician A says that this means the fluid
should be topped off with DOT 4, which has a higher boiling point than
regular brake fluid. Technician B says that this means that the fluid is
contaminated; all rubber parts in the system must be replaced and the system
flushed. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B.
Answer: The correct answer rs D, neither technician is right. Purple is the
color of silicone fluid, and only DOT 5 fluid should be used to top off the
reservoir.
◍ The front disc brake pads are being replaced on a vehicle with composite
rotors. The left front rotor is scored below the 'machine to' but not the
'discard' thickness. The right front rotor has minor heat checks but otherwise
checks out O
K. If cast rotors are the only available replacements, which of the following
is the proper course of action?
A. Machine both rotors, being careful not to exceed the 'discard' thickness.
B. Replace the left front rotor and machine the right front.
C. Replace both rotors.
D. Replace the left front rotor and leave the right front alone..
, Answer: The correct answer is C. Composite and cast rotors should not be
mixed on the same axle. Answer A is wrong because, as the question
indicated, the rotor is already worn past the 'machine to' dimension. even if
the rotor is not machined beyond the 'discard' thickness, this leaves no
allowance for wear in the future.
◍ Technician A says that any imperfection found in a phenolic caliper piston
warrants replacement. Technician B says that a phenolic caliper piston
should be protected with a block of wood when installing it into the caliper
bore with a C-clamp. Who is right?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B.
Answer: The correct answer is B. A phenolic piston should be protected to
keep it from being damaged when a C-clamp is used. Technician A is wrong
because minor surface imperfections are OK provided they do not enter the
dust boot groove area.
◍ A wheel speed sensor is being diagnosed using the OEM (original
equipment manufacturer) diagnostic scan tool. Technician A says to verify
wheel speed sensor operation, compare all four wheel speed sensor outputs
to vehicle speed on the data list. Technician B says the wheel's direction of
rotation can be verified by looking at the wheel direction on the scan tool
data list. Who is right?.
Answer: Both A and B
◍ This question has the word EXCEP
T. For this question, look for the choice that could NOT cause the described
situation. Read the entire question carefully before choosing your answer.
All of these would cause a low brake pedal, EXCEPT:.
Answer: Seized caliper pistonA seized caliper piston could cause the pedal
to be high with reduced braking power.
◍ All of the following could cause a hard brake pedal on a vehicle with power
, brakes EXCEPT:
A. An engine with the valves adjusted too tight
B. Brake fluid on the linings
C. A leak in the brake hydraulic system
D. A frozen caliper.
Answer: The correct answer is C. A leak in the hydraulic system wouldn't
cause a hard pedal but rather create the exact opposite condition due to the
hydraulic pressure loss. An engine with the valves adjusted too tight would
develop low vacuum. This would adversely affect the operation of the
power brake booster and cause a hard pedal. Brake fluid on the linings will
cause the friction material to grab resulting in a hard pedal, while a frozen
caliper would prevent retraction of the piston resulting in a similar
condition.
◍ A vehicle with 4-wheel disc brakes has a brake squeal. Technician A says a
defective proportioning valve could be the cause. Technician B says disc
brake squeal is often caused by movement of the disc brake pad during
braking. Who is right?.
Answer: B only To reduce disc brake squeal, all mating surfaces of the
brake should be clean and lubricated. Always use OEM recommended clips
and anti-squeal shims. To further reduce noise, do not machine a disc brake
rotor more than absolutely necessary. Technician A is wrong because the
proportioning valve only affects brake lockup and is not used on 4-wheel
disc brakes only on disc/drum combinations.
◍ On a car with single piston floating caliper disc brakes, the disc brake pad
between the caliper piston and the rotor is badly worn. The other brake pad
is slightly worn. Technician A says excessive rotor run out could be the
cause. Technician B says insufficient clearance between the pads and caliper
slider could be the cause. Who is right?.
Answer: Tech B only Insufficient clearance between the pads and caliper
slider causes the slider not to move and only applies one brake pad causing
only that pad to wear. Technician A is wrong because excessive rotor runout
will cause brake pulsations with no effect on wear.
