Automotive Service Technician Red Seal Review Flashcards

Practice questions and answers based on the Automotive Service Technician Interprovincial (Red Seal) Review Exam transcript.

When torquing cylinder head bolts, what two factors must be followed according to the manufacturer's manual?

The torque value and the torque sequence.

What does the last number marked on metric taps refer to?

It refers to the pitch of the thread in $\text{millimetres}$.

What is the specific crane signal for "lower load slowly"?

Place your arm out with the palm up, and make the lower load signal toward your palm.

How many times the chain's working load limit must the minimum ultimate load for a chain be?

It must be $4$ times the chain's working load limit.

What is the correct sequence of events (1 through 5) when de-energizing a relay circuit?

1. The initiating device is released or opened; 2. The relay coil is de-energized; 3. The core is no longer an electromagnet and releases the armature; 4. The spring returns the armature to its normal position; 5. The contacts return to their normally open position; 6. The power circuit opens and the lamp is de-energized.

To reduce warping, when is the best time to remove an exhaust manifold?

It is best to remove it once it has cooled.

When converting metric to imperial measurements for pressure, what number is $\text{kPa}$ divided by to get $\text{psi}$?

$\text{kPa}$ is divided by $7$ to get $\text{psi}$.

How is an $\text{EGR}$ sensor described?

It is a differential pressure sensor that compares exhaust pressure.

What must aluminum blocks be equipped with to prevent excessive cylinder wear?

They must be equipped with cast iron cylinder liners.

What tools can be used to check the main bearing bore size?

A dial bore gauge, an inside micrometer, or a telescoping gauge and outside micrometer.

How many members are in a non-lockup torque converter?

It is known as a three-member torque converter.

What are the two most common styles of driving recess found in automotive applications?

$Philips$ and $torx$.

Besides the ball check valve, what is the other type of check valve commonly used in automatic transmissions?

The poppet check valve.

What cause an engine lifter to rotate?

It will rotate due to the lobe taper.

Which class of portable fire extinguisher is recommended for a fire in a car's electrical system?

$Class\,C$.

What color are hoses used to supply oxygen generally?

They are generally $green$.

What does an identification marking on a piston ring indicate?

It indicates the top side of the ring.

Oxyacetylene equipment cannot be used to cut which three metals?

$Aluminum$, $copper$, and $nickel$.

What is the rule regarding the torque converter when removing a front wheel drive transmission?

Always remove the converter with the transmission.

What does a bolt head with six marks indicate?

It means that it is medium carbon alloy.

Why are aluminum pistons preferred over cast iron pistons?

Aluminum is preferred because its lighter weight causes less engine vibration, it provides a suitable bearing surface for the ring, and it has better heat conductivity.

What is NOT an electronic output from the $PCM$ on an electronically controlled automatic transmission?

The air conditioning clutch switch.

How are internal engine parts like the crankshaft cooled?

They are cooled by circulating engine oil.

What is the amount of pressure produced in an intake system above atmospheric pressure known as?

It is known as $boost\,pressure$.

In what position does a controller register a logic one bit when using a pull-up switch?

$closed$.

What does the abbreviation "$SA$" indicate on a wire?

It indicates that it has a sealed inner covering.

A piston slap noise in a newly rebuilt engine may be caused by what installation error?

The piston being installed backwards.

What is the basic function of pistons in an engine?

The basic function is to receive the force caused by combustion.

What condition would cause a valve spring retainer to fall off during engine operation?

The keeper grooves are worn.

What is the main function of a regulator besides maintaining constant delivery pressure?

To reduce the source pressure to an operating pressure.

At what depth should engine core plugs be installed?

They should be installed flush with the block.

What is a pulse width modulated ($PWM$) solenoid NOT used to control?

Controlling the air conditioning clutch.

What is the name of the matching groove cut into a shaft to accept a key?

The $keyway$.

What symptom indicates a center support bearing (steady bearing) needs replacement?

A continuous growl or whine at all speeds.

What are the three ways to disarm an air bag?

Disconnecting the connector at the lower steering column, removing the air bag system fuse, or disconnecting the battery negative cable.

What is the final adjustment performed during a wheel alignment?

The front toe.

What is the term for the outward and inward tilt of a wheel?

$Camber$.

What action can cause an electric power steering system to overheat?

Repeatedly turning the steering from stop-to-stop.

What are the main purposes of a transmission?

To provide a neutral, to provide a reverse, and to multiply torque.

What is the most common problem associated with hydraulic assist steering?

Fluid leaks.

Why is a damper or cardboard sleeve used in propeller shaft construction?

To help reduce torsional vibration.

What material is the center wire of high voltage spark plug cables usually made of?

Carbon-impregnated fibre.

Which type of driveshaft is connected between a fixed component and a wheel assembly?

$Halfshafts$.

In electronic diesel fuel injection systems, what does the acronym $PCM$ stand for?

$Powertrain\,Control\,Module$.

What meter is recommended for testing a removed diesel engine cylinder glow plug?

A digital ohmmeter.

How many digits are in a typical $OBD\,II$ diagnostic trouble code?

$5$-digit codes.

How is the pinion gear supported in a rack and pinion steering housing?

It is supported by needle roller bearings.

What specifically inflates an air bag?

An explosive device that starts a chemical reaction.

How does the speed of a distributor shaft compare to the speed of the crankshaft?

It is driven at $0.50$ times the crankshaft speed.

What part can be damaged if a manual transmission is left hanging unsupported during removal?

The $clutch$.

What is the most frequently serviced part of an ignition system?

The $spark\,plugs$.

What does fluid found in the bellows of a rack and pinion steering system indicate?

This indicates there is a leak in the seals.

What would cause a $FWD$ vehicle to vibrate when accelerating moderately from about $50\,km/h$?

This is an indication that the inner $CV$ joint is binding.

On the $GM$ fast start system, what is the crankshaft sensor used for?

It is used to correct timing of the sequential fuel injection.

What is the critical step to perform before servicing a steering column?

Disarm the air bag.

How are components connected in a waste spark ignition system?

They are connected in $series$ with each other.

When checking tires on an $AWD$ vehicle by rotating them ten times, within what distance should the markings appear from each other?

Within $2.5\,cm$ of each other.

What is a manual transfer case at the rear of a transmission used for?

To direct engine power to all wheels in a four wheel drive system.

At what pressure will a check ball in a quick take up valve unseat?

At approximately $70\,psi$.

What are three potential causes of oxides of nitrogen ($NOx$) emissions?

Lean air-fuel ratios, incorrect ignition timing, and high compression ratios.

When evacuating an air conditioner system, to what level should the pressure be lowered?

To at least $28\,Hg$.

Where is the pressurized fluid stored in an electro hydraulic brake system?

In an accumulator.

What kind of system is a brake system considered?

A $hydrostatic$ system.

What does a pressure differential valve do?

It is installed to warn the driver of a failure of either of the hydraulic systems.

What does an oil-soaked hose leak interfere with?

The $vacuum\,signal$.

What should be done during refrigerant recovery if the accumulator shows signs of frost?

Warm the accumulator with a hot wet cloth.

What are the approximate percentages of nitrogen and oxygen in air?

$78\,\%$ nitrogen and $22\,\%$ oxygen.

At what coolant temperature does the cooling fan generally turn on in an $AC$ system?

When it exceeds $100\,^{\circ}C$.

Effective September 1, $2000$, what is prohibited regarding motor vehicle air conditioning?

Charging systems designed for passengers with $Chlorofluorocarbons$.

What device prevents excessive pressure in a vehicle's propane tank due to heat?

A safety pressure relief valve.

How often is the $NV-246$ transfer case designed to respond to shifts?

One shift per $10\,seconds$.

What do occasional or slow-moving bubbles in an $AC$ system sight glass indicate?

The refrigerant is slightly low.

What mixture coats the pellets in a reduction type converter?

$70\,\%$ platinum and $30\,\%$ rhodium.

What does a Red warning label on a hybrid electric vehicle indicate?

High voltage over $30\,V\,ac$ is present and cannot be disabled.

When do $PCM$ controlled electric air pumps normally turn off?

When the air fuel mix is too rich.

When a magnetic field around a coil is at its maximum size, what is the coil called?

$Saturated$.

What is the self-discharge rate of a lead-acid battery between $20$ and $30\,^{\circ}C$?

Approximately $0.2\,\%$ of its charge per day.

What provides traction torque when a hybrid vehicle slowly accelerates while the $ICE$ is off?

$MG2$.

What is the function of a flow diffuser in a monolith converter?

To distribute the exhaust evenly over the entire honeycomb structure.

How many cells compose a common $12$-volt automotive battery?

$6$ cells.

What is recommended to use when soldering near electronic components?

A $heat\,sink$.

What is the most common hazard associated with hybrid electric vehicles?

Electrocution from a high voltage source.

Hypoid gear sets require oil with which $GL$ rating?

$GL\,5$.

What is a material said to have if its resistance decreases as temperature increases?

A $negative\,temperature\,coefficient$ of resistance.

A partially blocked fuel injector will cause what change in fuel trim?

A high value in all the long-term trim cells.

What part is normally pressed into the centre section of an axle housing?

$Axle\,tubes$.

At what temperature does a lead-acid battery have only $20\,\%$ power available?

$-20\,^{\circ}C$.

What technology do electrically heated front windshields use?

A conductive laminate between the layers of glass.

In remote entry security systems, what do $DDM$ and $BCM$ stand for?

$Driver's\,Door\,Module$ and $Body\,Control\,Module$.

Which type of electric brake controller regulates current to trailer brakes proportionally based on vehicle slowing rate?

The proportional controller.

Starter motors should not be run for more than how many seconds under load?

Not more than $30\,seconds$.

In charging system diagnostics, what does the acronym $MIL$ stand for?

$Malfunction\,Indicator\,Lamp$.