Vehicle Control

Steering, braking, backing and keeping the vehicle stable, including how anti-lock brakes work and how to recover from a skid.

55 practice questions with answers. These rules are the same in every state.

Vehicle Control quiz

Answer at your own pace. After each question you see the correct answer and why, and at the end a review of what you missed.

Quick quiz: 10 random questions on vehicle control; pass with 8 correct.

Vehicle Control questions with answers

Where should your hands normally rest on the steering wheel?
1. Both hands together at the top of the wheel
2. One hand at the top and the other in your lap
3. On opposite sides of the wheel, near the 9 and 3 positions
4. Inside the rim of the wheel for a firmer grip
Show answer

Answer C: On opposite sides of the wheel, near the 9 and 3 positions

Hands placed opposite each other near the middle of the wheel give smooth, balanced control and keep the arms clear of a deploying air bag.
You brake hard in a vehicle with antilock brakes and feel the pedal pulsing under your foot. What should you do?
1. Keep firm, steady pressure on the pedal and steer where you need to go
2. Release the pedal and then pump it rapidly until the vehicle has stopped
3. Lift off the pedal until the pulsing stops, then press it down again
4. Apply the parking brake as well to add extra stopping power
Show answer

Answer A: Keep firm, steady pressure on the pedal and steer where you need to go

The pulsing is the system releasing and reapplying the brakes so the wheels keep rolling, which is what lets you steer while braking. Pumping the pedal defeats it.
The rear of your vehicle begins to slide sideways on a slippery surface. What is the correct correction?
1. Brake hard and hold the wheel perfectly still until the vehicle settles down
2. Turn the wheel away from the direction of the slide, so as to counteract the movement of the rear
3. Ease off the accelerator and steer in the direction you want the front of the vehicle to go
4. Accelerate firmly and countersteer sharply to bring the rear end back into line
Show answer

Answer C: Ease off the accelerator and steer in the direction you want the front of the vehicle to go

Looking and steering toward your intended path lines the front wheels up with the direction of travel, while sudden braking or a sharp opposite input usually makes the slide worse.
Why is it risky to brake hard and steer sharply at the same moment?
1. The steering wheel locks up whenever the brakes are applied at the same time
2. Braking switches off the power steering until the pedal is released
3. The tires have a limited amount of grip that braking and turning must share
4. The brake lights stop working while the turn signal is flashing
Show answer

Answer C: The tires have a limited amount of grip that braking and turning must share

Each tire can deliver only so much grip, and asking it to slow the vehicle and change direction at once can exceed that limit and start a skid.
How can you check that you are keeping a safe following distance?
1. Count at least three seconds between the vehicle ahead passing a fixed object and your reaching it
2. Stay one car length back for every 10 mph of speed, whatever the conditions may be
3. Keep the vehicle ahead centered in your windshield and judge the gap from how large it appears to you
4. Match the gap that the driver behind you is keeping from your own vehicle
Show answer

Answer A: Count at least three seconds between the vehicle ahead passing a fixed object and your reaching it

Pick a fixed roadside object, start counting when the vehicle ahead passes it and make sure at least three seconds elapse before you reach it, adding more time in poor conditions.
What is the correct technique for backing a vehicle straight?
1. Rely on the mirrors alone and back out at your normal driving speed
2. Check behind the vehicle before getting in, then turn and look through the rear window while backing slowly
3. Back out quickly so that you spend less time blocking the traffic lane behind you
4. Watch only the backup camera and ignore what is happening at the sides, since the camera shows everything behind you
Show answer

Answer B: Check behind the vehicle before getting in, then turn and look through the rear window while backing slowly

Mirrors and cameras leave gaps close to the vehicle, so walk behind it first, then turn in your seat for a direct view and keep the speed low enough to stop instantly.
What is wrong with steering through a turn using the palm of one hand on the wheel?
1. It wears out the steering wheel and the power steering pump much faster than normal
2. It is illegal in every state and carries a fine
3. It causes the air bag to deploy during sharp turns
4. You have less control and cannot correct quickly if something goes wrong
Show answer

Answer D: You have less control and cannot correct quickly if something goes wrong

One-handed palming gives poor leverage and slow response. Use hand-to-hand or hand-over-hand steering with both hands so you can react instantly.
You turn the wheel but the front of the vehicle keeps sliding straight ahead on a slippery road. What should you do?
1. Turn the steering wheel even further in the same direction so the tires bite into the surface
2. Brake hard while holding the wheel fully turned
3. Ease off the accelerator and reduce the steering angle until the front tires grip again
4. Accelerate to push the front tires into the turn
Show answer

Answer C: Ease off the accelerator and reduce the steering angle until the front tires grip again

A front-wheel skid means the tires are asking for more grip than the surface can give. Less speed and less steering angle let them regain traction.
How should the inside rearview mirror be adjusted?
1. So you can see the driver's side of the vehicle and the lane beside it
2. So you can see the entire rear window without moving your head
3. So it shows the road just behind the rear bumper
4. So the back seat and passengers are fully in view
Show answer

Answer B: So you can see the entire rear window without moving your head

The inside mirror is for the view straight behind you. Framing the whole rear window from your normal seating position gives the widest useful view.
Why are tall vehicles such as SUVs and vans at extra risk in sudden steering maneuvers?
1. Their larger tires lose their grip much sooner than car tires on dry pavement
2. Their higher center of gravity makes them more likely to roll over
3. Their wider mirrors catch the wind and pull the vehicle sideways
4. Their engines produce more power than the brakes can handle
Show answer

Answer B: Their higher center of gravity makes them more likely to roll over

The higher a vehicle's mass sits, the more it leans in an abrupt turn, and a sharp swerve can tip it over. Smooth, gradual steering inputs are essential in tall vehicles.
The trailer you are towing begins to sway from side to side at highway speed. What should you do?
1. Brake hard to bring the trailer back in line quickly
2. Speed up so the trailer is pulled straight by the extra force
3. Steer sharply in the opposite direction of each sway to cancel the movement
4. Ease off the accelerator, hold the wheel steady and let the speed drop
Show answer

Answer D: Ease off the accelerator, hold the wheel steady and let the speed drop

Sway grows with speed and with sudden inputs. Reducing speed gently while keeping the steering steady lets the trailer settle behind you.
How does heavy cargo on a roof rack change the way a vehicle handles?
1. It improves stability by pressing the tires more firmly onto the road surface, so you can corner faster
2. It has no effect unless the load weighs more than the vehicle
3. It shortens stopping distance because the added weight increases grip
4. It raises the center of gravity, so the vehicle tips more in turns and needs gentler steering
Show answer

Answer D: It raises the center of gravity, so the vehicle tips more in turns and needs gentler steering

Weight carried high makes the vehicle lean more and roll over more easily, and extra weight lengthens stopping distance. Drive slower and steer smoothly with a loaded roof.
Is it a good idea to shift into neutral and coast down a long hill to save fuel?
1. Yes, as long as you keep your foot resting near the brake pedal the entire way down
2. No, you lose engine braking and some control of the vehicle
3. Yes, on dry roads with little traffic
4. Yes, but only in a vehicle with automatic transmission
Show answer

Answer B: No, you lose engine braking and some control of the vehicle

In neutral the engine cannot help slow the vehicle, so the brakes do all the work and can overheat. Stay in gear so the drivetrain helps hold your speed.
At highway speed, a large object suddenly appears in your lane and there is open space beside you. Which response is often the most effective?
1. Brake as hard as you possibly can and hope to come to a stop before you reach the object
2. Steer around it, since at speed you can often turn quicker than you can stop
3. Sound the horn and keep driving straight at a steady speed
4. Keep the wheel straight and pump the brake pedal repeatedly to shorten the stopping distance
Show answer

Answer B: Steer around it, since at speed you can often turn quicker than you can stop

Above roughly 25 mph, stopping distance is long while a lane change takes only a moment. When space is available, a controlled steer around the hazard avoids the impact.
When is it appropriate to use cruise control?
1. In heavy stop and go city traffic to keep an even speed
2. On a dry, open highway with light traffic
3. On winding mountain roads to reduce fatigue
4. When you are sleepy and want to rest your leg
Show answer

Answer B: On a dry, open highway with light traffic

Cruise control suits steady conditions where you rarely need to change speed. It is a poor choice in traffic, on curves, on slippery roads or when drowsy, because it removes you from the speed decision.
Study tip. Rule out the options you know are wrong first. Two plausible answers are easier to choose between than four.
In a vehicle with automatic transmission, which foot should operate the brake and accelerator?
1. The left foot for the brake and the right foot for the accelerator
2. Either foot, whichever is more comfortable
3. The left foot for both pedals
4. The right foot for both pedals
Show answer

Answer D: The right foot for both pedals

Using only the right foot prevents pressing both pedals at once and keeps the response the same in every vehicle you drive. The left foot rests on the floor or the footrest.
You are backing a trailer and want its rear to move to the left. Which way should you turn the steering wheel?
1. Move the bottom of the wheel to the left, which turns the top to the right
2. Turn the top of the wheel to the left, the same as when backing without a trailer
3. Keep the wheel straight and let the trailer find its own line
4. Turn the wheel fully to the left and then fully to the right in quick succession
Show answer

Answer A: Move the bottom of the wheel to the left, which turns the top to the right

A trailer moves opposite to the tow vehicle's steering when backing. Holding the wheel at the bottom and moving your hand in the direction you want the trailer to go makes this easier.
The stability control warning light flashes while you are driving through a curve. What does it mean?
1. The system is actively working to keep the vehicle under control, so slow down
2. The system has failed completely and the vehicle must be repaired before you drive any farther
3. The tires have lost pressure and should be checked at once
4. The transmission has shifted into a low gear for the curve
Show answer

Answer A: The system is actively working to keep the vehicle under control, so slow down

A flashing stability control light means the system is braking individual wheels because you are near the limit of grip. Ease off and drive more gently.
Which steering method gives the most control when you must turn the wheel a long way at low speed?
1. Sliding one hand around the rim while the other rests in your lap
2. Holding the wheel at the top with one hand and spinning it through
3. Hand over hand, feeding the wheel from one hand to the other
4. Pushing the wheel with a straight arm while the other hand stays still
Show answer

Answer C: Hand over hand, feeding the wheel from one hand to the other

Hand over hand keeps both hands on the wheel through a large turn, so you never lose the ability to correct quickly.
Why should your thumbs rest along the rim rather than hook inside the spokes?
1. It keeps your palms off the airbag cover, which must stay clear at all times
2. It stops the horn from sounding by accident when you turn the wheel hard
3. It gives a lighter grip, which is easier on your wrists over a long drive
4. A jolt can spin the wheel and injure hooked thumbs
Show answer

Answer D: A jolt can spin the wheel and injure hooked thumbs

A pothole or a dropped wheel can snap the wheel round violently, and thumbs hooked through the spokes are trapped when it happens.
How far should the driver chest be from the steering wheel?
1. As close as possible, so the arms stay bent and relaxed at the elbow
2. At least about ten inches
3. About three inches, so you can reach every control without leaning forward
4. As far back as the seat travel allows, even if the pedals become hard to reach
Show answer

Answer B: At least about ten inches

The airbag deploys with great force in the first instants of a crash, so about ten inches between your chest and the wheel is the recommended minimum.
You are backing straight down a driveway while looking over your right shoulder. Where should your left hand be?
1. On the gear selector, ready to shift as soon as you need to stop
2. On the bottom of the wheel, so the vehicle follows your hand naturally
3. At the top of the steering wheel, holding it with a firm grip
4. Off the wheel entirely, resting on the back of the passenger seat
Show answer

Answer C: At the top of the steering wheel, holding it with a firm grip

With one hand at the top of the wheel you can hold a straight course and make small corrections while your body is turned to look behind.
How do you avoid the sharp nod at the end of a stop?
1. Ease the pedal pressure off slightly just before the vehicle stops
2. Press the pedal harder in the last few feet so the stop is definite
3. Shift into neutral as soon as the vehicle has slowed to walking pace
4. Pull the parking brake on gently over the last few feet of the stop
Show answer

Answer A: Ease the pedal pressure off slightly just before the vehicle stops

The nod comes from the suspension unloading at the instant the wheels stop. Releasing a little pressure at the end lets the vehicle settle smoothly.
What is threshold braking?
1. Pressing and releasing the pedal in a fast rhythm until the vehicle stops
2. Braking only with the parking brake so the front wheels can still steer
3. Braking hard but staying just short of locking the wheels
4. Braking with the left foot while the right foot stays on the accelerator
Show answer

Answer C: Braking hard but staying just short of locking the wheels

A rolling tire grips better than a sliding one, so the shortest stop comes from pressure held just below the point where the wheels lock.
Your vehicle has antilock brakes. What should you never do in an emergency stop?
1. Pump the pedal up and down
2. Keep steady pressure on the pedal while steering around the hazard
3. Press the pedal as hard as you can and hold it there until you stop
4. Look toward the gap you want to reach rather than at the obstacle itself
Show answer

Answer A: Pump the pedal up and down

The system already releases and reapplies the brakes many times a second. Pumping the pedal interrupts it and makes the stop longer.

Source: nhtsa.gov
You brake hard on a wet road and need to steer around a stalled car. How do antilock brakes help you do that?
1. They cut engine power so the vehicle slows before you reach the obstacle
2. They stop the wheels locking, so the tires can still turn the vehicle
3. They shorten the stopping distance so much that steering is unnecessary
4. They tighten the steering so a smaller movement of the wheel is enough
Show answer

Answer B: They stop the wheels locking, so the tires can still turn the vehicle

Locked wheels slide and cannot change direction. By preventing lockup the system lets you brake at full force and steer at the same time.

Source: nhtsa.gov
On loose gravel or deep fresh snow, how does an antilock system affect the stopping distance?
1. It always cuts the distance roughly in half compared with locked wheels
2. It has no effect at all, because the system switches itself off below freezing
3. It shortens the distance because the wheels stay locked into the surface
4. It can lengthen it, although you keep the ability to steer
Show answer

Answer D: It can lengthen it, although you keep the ability to steer

On loose surfaces a locked wheel piles up a wedge of gravel or snow that helps it stop, so the antilock stop can be longer even though steering still works.

Source: nhtsa.gov
What most often starts a rear wheel skid?
1. Too much speed, braking or acceleration for the grip available
2. Steering with both hands placed near the top of the steering wheel
3. A tire pressure a few pounds above the figure on the door placard
4. Using the windshield wipers at the same time as the defroster fan
Show answer

Answer A: Too much speed, braking or acceleration for the grip available

A skid begins when what you ask of the tires exceeds what the surface can give, which is usually a matter of speed and of how abruptly you use the controls.
You correct a rear wheel skid and the back of the vehicle swings the other way. Why?
1. The antilock system has released the rear brakes and cannot reapply them
2. The front tires have lost their grip completely and are no longer steering
3. The rear tires have gripped again and are pushing the vehicle sideways
4. You steered too far, so be ready to correct back the other way
Show answer

Answer D: You steered too far, so be ready to correct back the other way

Over correcting sends the tail past straight and starts a second skid the opposite way. Steer smoothly and be ready to unwind the correction.
In plain words, what is understeer?
1. The vehicle turns more sharply than you intended and the tail comes around
2. The vehicle keeps going straight even though the wheels are turned
3. The steering wheel becomes very heavy and will not turn any further
4. The vehicle leans over so far in a turn that the inside wheels lift up
Show answer

Answer B: The vehicle keeps going straight even though the wheels are turned

Understeer means the front tires have run out of grip, so the vehicle takes a wider line than the one you steered.
In plain words, what is oversteer?
1. The steering feels loose because there is too much play in the linkage
2. The front of the vehicle pushes wide and will not follow the curve
3. The rear of the vehicle slides out and the car turns too sharply
4. The vehicle rolls toward the outside of the curve more than you expect
Show answer

Answer C: The rear of the vehicle slides out and the car turns too sharply

Oversteer means the rear tires have lost grip first, so the tail swings out and the vehicle turns more than you asked it to.
Why should you not switch the engine off while the vehicle is still moving fast?
1. The brake lights stop working, so drivers behind get no warning at all
2. You lose power steering and the steering may lock
3. The fuel pump keeps running and can flood the engine with unburned fuel
4. The antilock system stays on and will apply the brakes at their full force
Show answer

Answer B: You lose power steering and the steering may lock

With the engine off the steering becomes very heavy and on many vehicles the column can lock, so shift to neutral first and only shut down once stopped.
What can a loose or doubled up floor mat on the driver side cause?
1. It can slide forward and trap the accelerator pedal down
2. It can block the air vents and let the windshield fog over within seconds
3. It can wear through the carpet and expose the wiring underneath the floor
4. It can unbalance the vehicle enough to change how the front wheels track
Show answer

Answer A: It can slide forward and trap the accelerator pedal down

An unsecured mat, or a second mat laid over the first, can slip forward and hold the accelerator open. Use the mat clips and never stack mats.
The brake pedal goes to the floor and the vehicle does not slow. What should you try first?
1. Pull the parking brake up as hard and as fast as you possibly can
2. Switch the engine off so that the vehicle coasts to a halt on its own
3. Pump the pedal quickly to try to build pressure
4. Steer into the opposite lane where there is more room to run out of speed
Show answer

Answer C: Pump the pedal quickly to try to build pressure

Most vehicles have a split braking system, so rapid pumping can often build enough pressure to slow you. If it does not, use the parking brake gradually.
You are using the parking brake to slow a vehicle whose brakes have failed. How should you apply it?
1. All the way in one movement, so the rear wheels stop the vehicle at once
2. In short bursts of full pressure with a brief pause between each one
3. Only after the vehicle has already slowed to walking pace on its own
4. Gradually, holding the release so you can let it off if the rear slides
Show answer

Answer D: Gradually, holding the release so you can let it off if the rear slides

The parking brake works on two wheels only, so applying it hard can lock them and spin the vehicle. Keep the release held so you can back it off instantly.
You hear a bang and one of the front tires deflates while you are on the highway. What happens to the vehicle?
1. The steering goes completely dead and the wheel spins in your hands
2. The rear steps out sideways as though it were on a patch of ice
3. The brake pedal sinks to the floor and the vehicle slows on its own
4. It pulls strongly toward the side that failed
Show answer

Answer D: It pulls strongly toward the side that failed

The collapsed tire drags heavily on that corner, so the vehicle veers toward it. Hold the wheel firmly, keep your line and let the speed fall before leaving the road.
A rear tire blows out on the highway. How does the vehicle usually behave?
1. The steering becomes very heavy and the front of the car dives downward
2. The vehicle pulls hard toward the front left whatever side the tire is on
3. The back end weaves or fishtails from side to side
4. Nothing changes until you brake, when the vehicle spins toward the shoulder
Show answer

Answer C: The back end weaves or fishtails from side to side

A rear failure shows up as the tail wandering rather than a pull on the steering, so hold the wheel straight and let the speed drop gradually.
You have brought the vehicle under control after a blowout. What should you do next?
1. Signal and coast well off the road before stopping
2. Stop in the traffic lane at once and switch on your hazard lights
3. Carry on at reduced speed to the next town so a garage can look at it
4. Pull onto the left shoulder, which is usually wider than the right one
Show answer

Answer A: Signal and coast well off the road before stopping

Let the speed fall, signal, and leave the roadway as far from traffic as you can before you stop. Driving on a failed tire ruins the wheel and risks control.
Your right wheels have dropped onto a soft shoulder. Why should you not steer straight back onto the pavement?
1. The tires can catch the pavement edge and throw you across the road
2. The shoulder gravel would be dragged onto the pavement behind you
3. The suspension needs a moment to settle before the tires can grip again
4. The antilock system needs several seconds to detect the change of surface
Show answer

Answer A: The tires can catch the pavement edge and throw you across the road

A tire pressed against the edge of the pavement climbs it suddenly, and at speed that jolt can send the vehicle across the center line.
Why is heavy braking a poor idea while two wheels are still on a soft shoulder?
1. The brakes will fill with dust from the shoulder and stop working entirely
2. The two sides have different grip, so the vehicle can pull sharply
3. Braking pushes the vehicle further down the slope of the soft shoulder
4. The parking brake will engage on its own once the wheels lock on gravel
Show answer

Answer B: The two sides have different grip, so the vehicle can pull sharply

With one pair of wheels on pavement and the other on loose material, hard braking slows one side more than the other and swings the vehicle around.
You have loaded the trunk heavily. Why might oncoming drivers flash their lights at you at night?
1. The extra weight makes the tail lights burn brighter than they should
2. A loaded vehicle travels more slowly, which annoys the drivers behind you
3. The extra weight dims the low beams so they look like parking lights
4. The rear sits lower, so your headlights point higher and dazzle them
Show answer

Answer D: The rear sits lower, so your headlights point higher and dazzle them

Weight in the back tips the vehicle nose up and lifts the beam pattern, so low beams shine into the eyes of drivers coming the other way.
Where do you find how much weight your vehicle may carry?
1. On the sidewall of the tire, next to the maximum pressure figure
2. On a plate under the hood beside the engine identification number
3. On the placard in the driver door opening
4. On the registration document that must be kept in the glove compartment
Show answer

Answer C: On the placard in the driver door opening

The certification placard in the driver door opening gives the load limit and the recommended cold tire pressures for the vehicle as built.

Source: nhtsa.gov
You are towing a trailer and turning right at an intersection. What must you allow for?
1. The trailer will swing out to the left before it follows you around
2. The trailer will push the car forward when you brake during the turn
3. The trailer needs a tighter line than the car, so you should turn early
4. The trailer cuts the corner, so swing wider than usual
Show answer

Answer D: The trailer cuts the corner, so swing wider than usual

A trailer follows a shorter path than the towing vehicle, so its wheels track inside your line and can mount the curb unless you take the turn wide.
A trailer that sways badly at speed is often loaded the wrong way. What is the usual fault?
1. Too much of the load sits behind the trailer axle
2. The load is spread evenly from the front of the trailer to the back of it
3. The load has been placed as low as possible on the floor of the trailer
4. The load is tied down so tightly that the trailer springs cannot move
Show answer

Answer A: Too much of the load sits behind the trailer axle

Weight behind the axle lightens the hitch and lets the trailer wag the vehicle. Most of the load should sit ahead of the axle to keep weight on the hitch.
What should you check on the hitch before towing a trailer?
1. That the trailer tires are inflated well above the figure on their sidewall
2. That the coupler is locked and the safety chains are crossed underneath
3. That the chains hang straight down so they can drag along the pavement
4. That the trailer lights are disconnected so they cannot drain the battery
Show answer

Answer B: That the coupler is locked and the safety chains are crossed underneath

The coupler must be latched and pinned, and the chains crossed under the tongue so they cradle it if the coupling lets go.
Study tip. When two answers both seem legal, pick the one that is safer for everyone on the road. That is how most tests are written.
Which trailer lights must work before you drive away?
1. Only the tail lights, since the car signals are visible past the trailer
2. The tail lights, brake lights and turn signals
3. Only the brake lights, because the trailer is wider than the towing vehicle
4. Only the marker lights along the side of the trailer body
Show answer

Answer B: The tail lights, brake lights and turn signals

The trailer hides the vehicle lights from anyone behind, so its own tail, brake and turn signals have to work before you move.
How can you tell a tire has reached its wear limit without measuring it?
1. The tread pattern becomes noisier than it was when the tire was new
2. The tire starts to lose pressure faster than the other three tires do
3. The wear bars across the grooves become level with the tread
4. The sidewall begins to look shiny where it has rubbed against the curb
Show answer

Answer C: The wear bars across the grooves become level with the tread

Molded bars sit at the bottom of the grooves. Once the surrounding tread has worn down to them, the tire has reached the end of its safe life.

Source: nhtsa.gov
The tire pressure monitoring symbol lights up on your dashboard. What is the system telling you?
1. At least one tire is significantly underinflated
2. One of the tires has been inflated above the maximum on its sidewall
3. The spare tire in the trunk needs to be checked before your next long trip
4. The tread on one of the tires has worn below the legal minimum depth
Show answer

Answer A: At least one tire is significantly underinflated

The system warns when a tire falls well below the recommended pressure. Check all four with a gauge and inflate to the placard figure while they are cold.

Source: nhtsa.gov
How does driving on overinflated tires affect the vehicle?
1. It lengthens the braking distance because the tires run much cooler
2. It makes the steering very heavy at low speed and in parking lots
3. It makes the tires wear on both edges and gives a much softer ride
4. It gives a harsher ride and a smaller contact patch
Show answer

Answer D: It gives a harsher ride and a smaller contact patch

An overinflated tire bulges in the middle, so less rubber touches the road, grip suffers and the ride becomes hard. The center of the tread wears first.

Source: nhtsa.gov
What does a traction control system do?
1. It limits wheel spin when you accelerate
2. It applies the brakes automatically when a vehicle ahead of you slows down
3. It steers the vehicle back into the lane if you begin to drift out of it
4. It holds the vehicle at a set speed downhill without any use of the brakes
Show answer

Answer A: It limits wheel spin when you accelerate

Traction control cuts power or brakes a spinning wheel so the tires can grip when you pull away or accelerate on a slippery surface.

Source: nhtsa.gov
What does electronic stability control do that ordinary brakes cannot?
1. It shortens the stopping distance on ice by about half in every situation
2. It steers the vehicle for you whenever the road curves more than expected
3. It brakes single wheels to bring the vehicle back on your intended path
4. It stops the vehicle rolling backward when you pull away on a steep hill
Show answer

Answer C: It brakes single wheels to bring the vehicle back on your intended path

The system compares where you have steered with where the vehicle is actually going, then brakes individual wheels to pull it back into line.

Source: nhtsa.gov
What is the main limit of stability and traction control systems?
1. They only work while the vehicle is being driven in a straight line
2. They cannot create grip that the tires and the road do not have
3. They stop working once the outside temperature falls below freezing
4. They only operate below about 20 mph, which is why they help in parking
Show answer

Answer B: They cannot create grip that the tires and the road do not have

These systems manage the grip that exists. If you enter a curve too fast for the surface, no amount of electronics will hold the vehicle on the road.

Source: nhtsa.gov
When is switching traction control off sometimes useful?
1. When you need spinning wheels to rock out of deep snow or mud
2. When you are driving on a wet road and want a shorter stopping distance
3. When you are towing a trailer on the highway and want a steadier ride
4. When the road is icy and you want the wheels to grip the surface better
Show answer

Answer A: When you need spinning wheels to rock out of deep snow or mud

Rocking a stuck vehicle free needs the wheel spin that the system normally prevents. Switch it back on as soon as you are moving again.

Source: nhtsa.gov
The steering suddenly becomes very heavy while you are driving. What has happened and what should you do?
1. A front tire is flat, so brake hard and stop where you are
2. The wheel has locked, so switch the engine off and coast to a halt
3. The power steering has failed, so steer with more effort and pull over
4. The alignment has shifted, so keep driving and have it checked next week
Show answer

Answer C: The power steering has failed, so steer with more effort and pull over

Loss of power assistance leaves the steering usable but very heavy. Keep both hands on the wheel, slow gradually and pull off the road to check it.
The red brake warning light stays on after you release the parking brake. What should you do?
1. Keep driving and have the light checked at the next scheduled service
2. Pull the parking brake on and off a few times to reset the switch
3. Ignore it if the pedal still feels normal under your foot at low speed
4. Stop safely and have the brakes checked before driving on
Show answer

Answer D: Stop safely and have the brakes checked before driving on

With the parking brake released, that light points to low fluid or a fault in one half of the braking system, which can leave you with very little braking.