Ontario Air Brake (Z): Speed, weight, heat and ABS

All 21 questions in this test

Every question and its answer choices. The correct answers and explanations appear when you take the test above.

1. In extreme cases, what can severe brake fade lead to?

   1. Higher air pressure in the tanks
   2. Automatic release of spring brakes
   3. Being unable to slow or stop
   4. Shorter stopping distances

2. The ABS malfunction lamp comes on. What braking do you still have?

   1. Regular brake function
   2. No service brakes at all
   3. Spring brakes only
   4. Trailer brakes only

3. Should you expect ABS to shorten your stopping distance?

   1. Yes, by about half the distance
   2. Yes, when the trailer also has ABS
   3. No, it prevents lock, not distance
   4. Yes, but only on dry pavement

4. What do engine brakes and retarders help you avoid?

   1. Pushrod measurement
   2. Compressor cut-in
   3. Low tire pressure
   4. Excessive brake temperature

5. What can happen if you load a truck beyond its rated capacity?

   1. Only fuel consumption goes up
   2. The brakes may not stop it safely
   3. The governor raises cut-out pressure
   4. The brakes adjust to the extra load

6. Why might a driver not notice brakes that are slightly out of adjustment?

   1. Normal driving rarely needs full braking
   2. The ABS light hides the problem
   3. Out-of-adjustment brakes feel stronger
   4. Spring brakes cover the difference

7. If you double your vehicle's weight, what happens to stopping distance?

   1. It becomes four times longer
   2. It triples
   3. It doubles
   4. It stays the same

8. What is brake fade?

   1. The delay as air travels to the wheels
   2. Weaker brakes as they heat up
   3. A slow leak from the supply tank
   4. Wear marks on the inside of the drum

9. As speed or weight goes up, how must you use the brake pedal to get the same stop?

   1. Use the trailer hand valve instead
   2. Press it more lightly than usual
   3. Press it further
   4. Pump it rapidly several times

10. You double both your load and your speed. How does stopping distance change?

    1. It becomes about four times longer
    2. It becomes about six times longer
    3. It stays roughly the same
    4. It becomes about eight times longer

11. Once pushrod stroke passes the adjustment limit, what happens to brake force?

    1. It stays at full strength
    2. It increases slightly
    3. It falls off rapidly toward zero
    4. It shifts to the other axle

12. How often does Ontario law require air brake adjustment to be checked?

    1. Once a week
    2. Only at the annual inspection
    3. At least once each day
    4. Once a month

13. If you double your speed, how much longer is your stopping distance?

    1. About four times longer
    2. About eight times longer
    3. About three times longer
    4. About twice as long

14. How can out-of-adjustment brakes be detected?

    1. By watching the low-air warning light
    2. Only by a reliable inspection
    3. By listening carefully while driving
    4. By how the brake pedal feels

15. When does a vehicle have its full braking ability?

    1. When every brake is in adjustment
    2. Whenever the tanks are above 100 psi
    3. Whenever the ABS warning light is off
    4. Whenever the spring brakes are released

16. What does ABS mainly help you keep during hard braking?

    1. Cooler brake drums
    2. A shorter stopping distance
    3. Steering control
    4. Higher air pressure

17. What happens to a vehicle when a wheel locks and the tire skids?

    1. Its air pressure rises
    2. It stops in a shorter distance
    3. It loses steering control and stability
    4. It automatically engages ABS on all axles

18. Which driving situation builds the most heat in the brakes?

    1. Repeated braking down a long hill
    2. Idling for an hour at a loading dock
    3. Cruising at a steady highway speed
    4. Driving on a flat and empty road

19. Which habit helps keep brake temperatures down?

    1. Leaving a safe following distance
    2. Coasting in neutral down long grades
    3. Riding the brake lightly on all hills
    4. Braking hard and late at every stop

20. How long can the brake application delay be in an air brake system?

    1. Up to about two seconds
    2. Up to about one-half second
    3. Up to about five seconds
    4. There is no measurable delay

21. Where is the ABS warning lamp for a trailer usually mounted?

    1. Inside the trailer near the kingpin
    2. Under the trailer's rear bumper
    3. On the trailer's landing gear
    4. Where you can see it in the mirror