Automotive Service Technician Red Seal Review Exam

Comprehensive practice questions covering automotive systems including transmissions, electrical, braking, steering, and engine diagnostics based on the Red Seal review exam transcript.

According to the WHMIS system, what does the pictogram showing materials hazardous to the ozone layer represent?

Materials that cause hazardous effects specifically to the ozone layer.

When a shift valve in an automatic transmission is blocking fluid and preventing component application, what state is it in?

It is closed.

How does an automatic transmission function regarding its internal application components?

By hydraulically applying and releasing bands and clutches.

In a basic four-speed electronically controlled automatic transmission, what is the state of the shift solenoids in "O/D Second gear"?

$A$ – off, $B$ – on, $C$ – off.

What is the standard design for radiators in most modern-day vehicles?

The cross-flow design.

Which CAN protocol type is typically utilized for transmission control and engine management?

CAN C.

How is a Valley Forge wiring diagram oriented regarding electrical polarity?

The positive is at the top and the ground is at the bottom.

What is the primary use of check valves in automatic transmissions?

They are used as one-way valves.

Why is the adjustment of transmission manual linkage critical?

Adjustment is important to have the valve properly aligned in the valve body.

What are the common consequences of worn ring grooves on an engine piston?

The rings will rock back and forth, combustion gases will blow by the rings into the crankshaft, and oil consumption will occur.

Which aspect of transmission operation is affected by an incorrect TV setting, a defective modulator, or the type of fluid used?

Shift feel.

What is the most common design type for a vehicle muffler?

The reverse-flow design.

What does it mean if an automatic transmission fluid has good oxidation stability?

The fluid is resistant to deterioration over long service periods.

What is the primary function of a data bus in vehicle electronics?

To carry binary signals.

Which specific type of fuse is identified as a blade fuse in the transcript?

Autofuse.

What is the purpose of the ports on the exhaust side of a cylinder head?

They are used to direct the exhaust gases from the valves to the exhaust manifold.

How is an EGR sensor described in terms of its measurement method?

It is a differential pressure sensor that compares exhaust pressure.

What is the structural function of the engine block?

To support bottom end components and the crankshaft with a minimum of flexing.

Which device in an electronically controlled transmission senses load changes to trigger the PCM to increase line pressure?

The manifold absolute pressure sensor.

In a conventional three-member torque converter, where does the fluid flow out?

It flows out between the stator support and the turbine shaft.

Which shackle type is most commonly used in rigging applications?

Anchor type with screw pin.

What does it indicate if all pressures in an automatic transmission are low at idle?

It indicates there is a plugged filter.

In the context of cutting torches, what is torch inclination relative to?

The direction of travel.

What is the data bus configuration speed for the CAN A protocol in normal mode?

$33.33\,kbps$.

Most transmissions will not perform a part-throttle downshift above which approximate speed?

$50-60\,km/hr$.

What gas is present in excess in a carbonizing flame?

Acetylene.

Under WHMIS, what is a supplier’s responsibility regarding hazardous products?

To ensure that the hazardous products are properly classified as per the hazardous products regulations.

What are the divisions for pressure in the SI system?

$mPa$.

What is the function of shielding on a wire?

Protection from magnetic interference.

What kind of pressure readings will be produced by aerated fluid during an automatic transmission test?

Lower than normal pressure readings.

How are pistons for high performance or severe duty gasoline engines typically manufactured?

By forging.

In a gear set, what happens to torque and speed when a small input gear drives a larger gear?

Torque will be increased while the speed is reduced.

If a manual transmission has a gear reduction of $3:1$ and the engine speed is $1200\,rpm$, what is the output shaft speed?

$400\,rpm$.

What is the maximum allowed resistance for spark plug cables per $30\,cm$ of length?

$10\,\Omega$.

What color coding is used for the electrical wire going to the steering column air bag?

Bright yellow or bright orange.

If the clutch housing is part of the transmission case, what must be removed before raising the vehicle on a hoist?

The upper clutch housing bolts.

Why is the waste ignition system named as such?

Because one spark from a spark plug always does nothing.

What tool does a technician use to check drive shaft angles?

A drive shaft angle gauge.

What does a milky color in hydraulic assist steering fluid indicate?

There may be an internal leak in the pump.

What are clutch friction materials typically made of?

Ceramic materials, metallic materials, and non-metallic materials.

What are the two parts of a diesel fuel injection system?

A low-pressure primary system and a high-pressure secondary system.

What is the control behavior of a shock absorber with a ratio of $80/20$?

It controls $80\%$ on extension and $20\%$ on compression.

To which section of a hydraulic assist steering gear do the fluid lines connect?

The valve section.

Where are sub-frames typically located on a vehicle?

On both the front and rear of some vehicles.

Which design of manual transmission floor shift mechanism rarely requires adjustments?

The internal design floor shift mechanism.

What is the function of the flow control valve in a hydraulic assist steering pump?

To maintain the same flow at all engine speeds.

What component failure can cause a manual transmission to lock in one gear?

A broken shift rail.

What is the name of the driveshaft that transfers power between fixed components like the final drive and transmission?

Propeller shaft.

What is the maximum voltage that can be applied to spark plug cables?

$50,000\,V$.

What is the first step in removing a manual transmission from a vehicle?

Disconnect the battery ground cable.

What component holds directional control valve components in alignment?

The torsion bar.

When adjusting caster, why would a technician set the right side to be more positive than the left?

To ensure the vehicle pulls slightly towards the curb or ditch.

What can cause double or "ghost" secondary ignition waveforms?

A lean mixture, intermittent fuel system malfunction, or sticking valves.

What is the recommended tool usage for removing high-pressure fuel injection lines from injectors?

Use two wrenches to loosen the lines.

Which type of hydraulic steering pump produces usable pressure only when the outlet is restricted?

The demand pump.

What are vehicle springs designed to do?

Support the vehicle and its load, and absorb road shock.

What occurs in a vacuum booster during the "holding" position?

The diaphragm is moving ahead and brakes have begun to apply.

If a brake pedal sinks slowly to the floor, what is the likely source of the problem?

It is usually a master cylinder problem.

On an AWD vehicle with transfer clutch control, what is the result of a small duty ratio?

A strong clutch connection.

How is the ambient temperature sensor for an AC system described?

It uses a thermistor which measures outside air.

What is the standard amount of driver effort, in Newtons ($N$), to apply foot or hand operated park brakes?

$500\,N$.

What are the components of the encoder motor on a NV-246 transfer case?

A DC motor and a gear reduction assembly.

What is a characteristic of a variable displacement orifice tube system?

Pressure switches on the high side protect the compressor if refrigerant pressure is not within specifications.

In a non-servo brake, what is a "reverse acting shoe"?

A shoe that self-energizes when the vehicle is reversing.

By which year were CFC-based and HCFC-based refrigerants to be phased out?

2020.

Why is one reservoir larger in tandem master cylinders?

One half is serving disc brakes while the other serves drum brakes.

What energy conversion takes place in a braking system?

Kinetic energy to heat energy.

What type of fuel injector is generally used by TBI systems?

Bottom Feed fuel injector.

What is a distinguishing feature of an internal sensing expansion valve in AC systems?

It does not use an external sensing bulb on the evaporator outlet side.

What does the term "recycling" refer to in air conditioning maintenance?

The restoration of a recovered refrigerant.

What is the maximum allowed tapered wear on disc pads for sliding or floating calipers?

$0.3\,mm$.

Why is a ground lead to the earth needed when transferring fuel between tanks?

To bleed off any static electricity.

What material have calipers historically been made of?

Cast iron.

What characterizes a Type 2 natural gas storage cylinder?

A metal liner reinforced with fiberglass around the middle section.

What is the effect of grounding an oxygen sensor on fuel trim values?

It causes them to hit the extreme end of their range.

What is the shift response frequency for the NV-246 transfer case?

One shift per 10 seconds.

In brake mechanics, what is the "primary shoe"?

The first shoe from the actuating force in the direction of drum rotation.

What are the thin metal nuts used to hold a brake drum in place?

Tinnerman nuts.

What type of hose is required for propane-powered vehicles?

Type III hose.

Which specific DOT brake fluid is categorized as very hygroscopic?

DOT 4.

In a dual servo park brake design, is the shoe against the anchor when first applied?

No, it will not be against the anchor.

In a hybrid high voltage boost mode, if voltage increases by a factor of 20, what happens to the current?

The current will be reduced by a factor of 20.

To increase pinion bearing preload, what must be done to the shim thickness?

Decrease shim thickness.

What is the effect of a partially blocked fuel injector on fuel trim?

It will cause a high value in all the long-term trim cells.

When correcting an "out" contact pattern in gear sets, how must the pinion be moved?

The pinion must be moved in.

What substance is mixed with water to neutralize sulphuric acid in a lead-acid battery?

Baking soda.

What should a technician wear when handling static-sensitive electronic components?

A grounded wrist strap.

What are the stationary and rotating parts of a generator called, respectively?

The stationary part is the stator and the rotating component is the rotor.

What are the typical secondary voltage system components in a hybrid electric vehicle?

Inverter/drive controller, Traction motor/generator, and High voltage battery.

What is the minimum recommended impedance for an ohmmeter testing electronic circuits?

10 million ohms ($10\,M\Omega$).

What is a distinguishing characteristic of a digital EGR valve?

It does not require engine vacuum to operate.

In air management, where is the relief valve usually located?

It is normally built into the air pump.

What is meant by a material having a "positive temperature coefficient of resistance"?

The resistance of the conductor increases as the temperature increases.

How is flux line direction determined using conventional current flow theory?

By using the right-hand rule for conductors.

What is a characteristic of an electric air pump in terms of its placement?

The pump can be located anywhere in the engine compartment.

What is required for an automotive catalytic converter to facilitate effective reactions?

The catalyst must be hot.

Which final gear assembly type has a small load contact area?

Beveled spur.

What is the state of air delivery during deceleration in normal closed loop operation of air systems?

Air is diverted to the atmosphere.

In diagnostic scan tools, what is a "hard code"?

A failure that is present at the time of testing.

How much more starter current do diesel engines require compared to equivalent gasoline engines?

$50\%$ more.