South Dakota CDL — General Knowledge: Signals & Pavement Markings Practice Test

Question 1

At dusk in rain, the manual says to turn on your headlights and use the low beams. Why low beams?

Accepted Answer

High beams can bother people in daylight too — To be seen in poor light, drivers should use headlights rather than only the identification or clearance lights. Low beams are specified because high beams bother people by day as well as by night.

Answer

High beams drain the battery faster

Answer

Low beams reach farther in rain

Answer

High beams are illegal before sunset

Question 2

In fog, what reason does the manual give for turning on your four-way flashers?

Accepted Answer

Vehicles coming up from behind get a quicker chance to notice you — The fog advice includes switching on the 4-way flashers. The stated purpose is to give drivers approaching from the rear an earlier opportunity to see your vehicle.

Answer

They cut through fog better than headlights

Answer

They are required by federal rule whenever the windshield wipers are on

Answer

They warn oncoming traffic to dim its lights

Question 3

South Dakota's merge-or-slow rule applies when a stopped vehicle is using which warning light colors?

Accepted Answer

Amber, yellow, or blue — The rule is triggered by a stopped vehicle showing amber, yellow, or blue warning lights. Drivers then merge away on multi-lane highways or slow down on two-lane highways.

Answer

Red only, as on an ambulance

Answer

White or green

Answer

Red or white

Question 4

At which railroad crossings does the manual say to be especially alert?

Accepted Answer

Those that have no gates or flashing red light signals — Warning signals, gates, and flagmen should never be the only thing a driver relies on. The manual singles out crossings without gates or flashing red lights as places to be particularly watchful.

Answer

Those that have both gates and bells

Answer

Those located inside the limits of a city or town, and no others

Answer

Those with more than two tracks only

Question 5

You must drive slowly and want to alert the drivers behind you with your emergency flashers. What caution does the manual attach?

Accepted Answer

Use them only where legal; flasher laws vary by state — The manual suggests the flashers for slow driving, with the condition that it be legal. It points out that the laws on flasher use are not the same in every state and tells drivers to check them.

Answer

Never use them above 15 mph

Answer

Use them only at night

Answer

Use them only when hauling hazardous materials

Question 6

During the in-cab check of the seven-step inspection, a trailer's left rear yellow lamp stays lit. What does that tell you?

Accepted Answer

The trailer's ABS is not working properly — The dash ABS indicator should come on and then go off. For trailers, a yellow lamp on the left rear that stays lit means the antilock system is not working as it should.

Answer

The trailer's parking brake is set

Answer

The left turn signal is stuck on

Answer

The trailer's battery is charging

Question 7

An oncoming vehicle's headlights are glaring at night. Where does the manual tell you to look?

Accepted Answer

Slightly right, toward a right lane or edge marking — Drivers should not look straight at oncoming lights. The manual says to look slightly to the right, using a right lane or edge marking as the reference if one is available.

Answer

Directly at the oncoming lights, to judge their distance

Answer

At the center line, to hold your lane position

Answer

Down at the instrument panel until the vehicle passes

Question 8

Which lights does the manual tell you to turn on when you make a required full stop at a railroad grade crossing?

Accepted Answer

The four-way emergency flashers — When a stop at a grade crossing is mandatory, the driver checks for traffic behind while stopping gradually and switches on the four-way emergency flashers.

Answer

The high-beam headlights

Answer

The left turn signal

Answer

The clearance lights only

Question 9

Just before starting the walk-around in Step 5, which turn signal does the manual have you turn on?

Accepted Answer

The right turn signal — Step 5 ends its light setup by turning on the right turn signal and then starting the walk-around. The left turn signal is checked later, in Step 6.

Answer

The left turn signal

Answer

Neither; turn signals are checked only in Step 6

Answer

Both, by way of the four-way flashers

Question 10

At night, when it is legal, how can you let a vehicle you are about to pass know you are there?

Accepted Answer

Flash your lights from low beam to high beam and back — When passing, assume the other road user has not seen you. Where legal, the manual suggests a light tap of the horn, or at night a flash from low to high beam and back.

Answer

Switch to high beams and leave them on until you are past

Answer

Turn on the four-way flashers

Answer

Turn the headlights off briefly

Question 11

On the walk-around inspection, what colors should side-marker lights and side-marker reflectors be?

Accepted Answer

Red at the rear and amber elsewhere — The inspection guide gives the proper color for side-marker lights and reflectors as red at the rear, with the others amber.

Answer

Amber at the rear and red elsewhere

Answer

White at every position

Answer

Red at every position

Question 12

In Step 4 of the seven-step inspection, which lights do you switch on before getting out of the vehicle?

Accepted Answer

The low-beam headlights and the four-way emergency flashers — After setting the parking brake and shutting off the engine, Step 4 has you turn on the headlights on low beam along with the four-way flashers. You then get out and check them from the front.

Answer

The high beams and the left turn signal

Answer

The parking lights only

Answer

The stop lights and the backup lights, with a helper on the pedal

South Dakota CDL — General Knowledge: Signals & Pavement Markings practice test

Study questions with answers

1. At dusk in rain, the manual says to turn on your headlights and use the low beams. Why low beams?

2. In fog, what reason does the manual give for turning on your four-way flashers?

3. South Dakota's merge-or-slow rule applies when a stopped vehicle is using which warning light colors?

4. At which railroad crossings does the manual say to be especially alert?

5. You must drive slowly and want to alert the drivers behind you with your emergency flashers. What caution does the manual attach?

6. During the in-cab check of the seven-step inspection, a trailer's left rear yellow lamp stays lit. What does that tell you?

7. An oncoming vehicle's headlights are glaring at night. Where does the manual tell you to look?

8. Which lights does the manual tell you to turn on when you make a required full stop at a railroad grade crossing?

9. Just before starting the walk-around in Step 5, which turn signal does the manual have you turn on?

10. At night, when it is legal, how can you let a vehicle you are about to pass know you are there?

11. On the walk-around inspection, what colors should side-marker lights and side-marker reflectors be?

12. In Step 4 of the seven-step inspection, which lights do you switch on before getting out of the vehicle?

More CDL — General Knowledge topics

Practice Signals & Pavement Markings in another state