ASE S1: Body Systems And Special Equipment Test! Book Quiz

A booster pump is responsible for improving coolant circulation in a system. Coolant plays a crucial role in maintaining the optimal temperature of an engine. By improving the circulation of coolant, the booster pump helps in efficiently transferring heat away from the engine, preventing it from overheating. This ensures that the engine operates at its optimal temperature, enhancing its performance and longevity.

The correct answer is A. If the motor is receiving
12 volts and not operating in either direction, suspect a
defective motor

The correct answer is C. The maximum concentration
of coolant solution should not exceed 50 percent
coolant and 50 percent water for proper cooling
system protection.

The correct answer is D. A school bus fire extinguisher
must meet DOT requirements, must be
mounted in the driver’s area and the extinguisher
should be inspected for proper pressure at least
monthly

The correct answer is D. Compression leakage
puts hot gases into coolant, which not only is the
direct cause of the bubbles, but also causes coolant
loss. This happens because the gases constantly build
system pressure to the point where the cap opens. Too
much coolant in the system would empty through the
overflow. A clogged radiator would cause overheating.
A stuck-open thermostat would cause the coolant to
build even less pressure than is normal, meaning no
coolant loss would occur.

The correct answer is A. Radiator shutters are designed
to control air flow across the radiator core tubes.
They employ horizontal vanes, much like window
blinds, that open and close as a temperature sensor
dictates. These shutters maintain a certain coolant temperature
for efficient operation of the cooling system in
a specified temperature range.

The correct answer is D. Cooling system pressure
is maintained by the use of the radiator pressure cap. A
defective fan clutch will not allow the efficient transfer
of heat from the coolant to the atmosphere. A defective
water pump will not allow proper coolant circulation,
and a defective thermostat, depending on the condition,
will either overheat or overcool the engine.

The correct answer is C. A leaking heater core often leaves a residue of antifreeze (which does not readily evaporate) on the windshield.

The correct answer is D. Low fluid level will not
cause the lift to leak down. All of the other answers will
cause some type of bypassing of fluid from pressurized
areas, thereby allowing the lift to leak down.

The correct answer is D. A disengaged clutch-type
radiator fan would not cause low heater output.

The correct answer is C, both technicians are
right. According to Federal Motor Vehicle Safety Standards,
each reflector shall be a collapsible equilateral
triangle, with legs not less than 17-in. long and not less
than 2-in. wide. The front and back of the exposed leg
surfaces shall be covered with red reflective material
not less than 1/2-in. in width.

The correct answer is A. The vehicle should be
taken out-of-service until repairs can be made if any
of the following conditions exist: if there is any crack
in either frame rail or any crossmember; if there is any
loose or missing rivet or other fastener securing a crossmember
to the frame.

The correct answer is A. A first aid kit should be
mounted in an easily accessible location in the driver’s
area. The kit should be a type III classification (for portable
use in mobile and/or outdoor settings where the
potential for damage to the contents due to environmental
factors and rough handling is significant).

The correct answer is C, both technicians are right. An air blockage could prevent adequate coolant flow to the heater core and a defective water valve may block coolant flow if it does not open.

The correct answer is A. The solenoid valve is
designed to dump the air when the stop arm is being
closed. A leaking air line would most likely cause the
arm not to open.

The correct answer is C, both technicians are
right. Ethylene glycol is the most common chemical
base for antifreeze. Propylene glycol is safer for the environment.

The correct answer is B. Extended life, or fully
formulated coolants do not require supplemental coolant
additives, and can be used in ‘Fill For Life’ systems.
These systems incorporate a spin-on coolant filter that
senses the corrosion level of the coolant and releases
an SCA treatment to keep the coolant performing up
to optimum levels. Cartridges with an SCA supply are
available, but be careful not to use one along with an
SCA additive.

The correct answer is B. A short to ground will
cause the alarm to activate. A defective alarm would
not operate at all, and an open would not allow current
to flow at all.

The correct answer is C. NHTSA decided that
the best way to provide crash protection in large school
buses is through a concept called ‘compartmentalization.’
This requires that the interior of large buses
provide occupant protection so that occupants are protected
without the need to buckle-up. Occupant crash
protection is provided by a protective envelope consisting
of strong, closely-spaced seats that have energyabsorbing
seat backs.

The correct answer if B. School bus exits are generally
based on the designated seating capacity of the
vehicle. The exits must be clearly identified with retro
reflective tape to guide occupants exiting the vehicle in
case of an emergency.

The correct answer is C, both technicians are
right. On buses equipped with catalytic converters, the
heat of the converter can disguise coolant leaking into
the exhaust. Because of the high temperatures generated
by the converter, the coolant will heat into such a
fine vapor that the leak may not be noticeable. Technician
B is right because if the heater core is blocked, it
will not heat up properly and therefore not allow sufficient
heat to enter the bus.

The correct answer is C, both technicians are
right. Since the electric fan depends on coolant temperature
to run, a faulty temperature switch may not
correctly interpret coolant temperature. Therefore, the
electric fan may not operate. Also, a thermostat that
is stuck open will cause lower-than-normal engine
temperatures, causing the coolant to be cooler than it
should be when circulating through the engine. In this
case, the fan may not operate.

The correct answer is A. Rather than requiring
passenger seat belts on large school buses, NHTSA
decided that the best way to provide crash protection
to passengers is through a concept called ‘compartmentalization.’
This requires that the interior of large buses
provide occupant protection so that occupants are protected
without the need to buckle-up.

The correct answer is B. Electronic stop arms
employ micro switches to control stop arm closure.
Return springs are used on air and vacuum operated
systems.

The correct answer is A. When the seat belt switch
is stuck in the closed position, current is allowed to
flow causing the warning buzzer to sound and the light
to illuminate.

The correct answer is A. Hydraulic lifts tend not
to work as efficiently in cold weather. Most electric
lifts are lighter in weight than their electro-hydraulic
counterparts, and operate consistently in temperature
extremes.

The correct answer is D, neither technician is
right. While no Federal requirement exists for seat
belts on large school buses, states and localities are free
to install them if they feel it is in the best interest of
safety in their area. Small school buses, those with a
GVWR under 10,000 pounds, must be equipped with
lap or lap/shoulder belts at all designated seating positions.
Since their sizes and weights are closer to those
of passenger cars and trucks, seat belts in these vehicles
are necessary to provide occupant protection

The correct answer is A. Federal Motor Vehicle
Safety Standards (FMVSS) were set to monitor and
regulate motor vehicle safety. As the years passed, new
standards were written with many of them encompassing
school buses. As vehicles became more and more
complicated, and new safety features were made available,
standards had to be added or updated to cover the
particular safety enhancements built into each vehicle.
All vehicle manufacturers, no matter what kind of vehicle,
must comply with FMVSS regulations.

The correct answer is C, both technicians are
right. The fan switch directs current flow through one
or more resistors to reduce blower motor speed. Temperature
is controlled by increasing or decreasing the
flow of coolant through the heater core.

The correct answer is C. When filling the engine
with coolant to purge air, the fill rate should not exceed
5 gallons per minute.

The correct answer is B. If both hoses leading to
the heater core are hot, coolant is circulating through
the heater core. One hose that is significantly cooler
than the other would indicate a clogged heater core.
However, if the temperature control cable is misadjusted,
the temperature blend door may not allow
enough warm air to enter the bus for sufficient heating.

The correct answer is D, neither technician is
right. Interlock switches are designed to disable the
lift or school bus when safe conditions do not exist. A
blown fuse or circuit breaker wouldn’t allow the liftgate
to operate at all.

The correct answer is A. The vacuum actuator
contains a spring-loaded diaphragm, one side of which
is connected to the vacuum source. The other side is
attached to an arm that moves the air door. Leaks or
disconnected hoses will cause the doors to stay in the
wrong position, thereby not allowing sufficient heat to
enter the bus.

The correct answer is C, both technicians are right. To
test a mechanical clutch, you can use either a thermometer or
an electronic temperature probe on the radiator near the inlet,
and connect a timing light to the engine. Start the engine and
strobe the fan to ‘freeze’ the blades, noting the engine speed.
When the engine warms up, the fan should increase speed
and the blades will appear to be moving in the strobe light. As
the temperature drops, the fan should slow down. To speed
the heating and cooling, block the radiator, but remember to
remove your obstruction before the engine overheats.

The correct answer is D. Each vehicle must be
equipped with a restraining barrier forward of any
designated seating position that does not have the rear
surface of another passenger seat.

The correct answer is C, both technicians are right. Generally, if one of the blower speeds does not work, the problem is a faulty resistor. If the high speed does not work, the problem could be the high-speed relay or fuse.

The correct answer is A. If a door is shared by two
functions, it may bind halfway, routing heat in two different
directions. A vacuum leak at the heater control
valve will cause the valve to either stay open or closed
(depending on the configuration). The heater control
valve only controls the temperature of the inside air
and does not affect air routing.