AIR BRAKES TEST
1. You should know that your brakes are fading when?
a. You have to push harder on the brake pedal to control your down
hill speed
b. The brake pedal feels spongy when you apply pressure
c. Pressure on the brake pedal is released and speed increases
2. If the spring brakes are on when should you push the brake pedal?
a. Only when driving down hill
b. Only on a slippery road
c. Never
3. Repeatedly pressing and releasing (fanning) the brake pedal may result in?
a. A loss of air pressure
b. A build up of air pressure
c. No change in brake air pressure
4. The driver must be able to see a low air pressure warning which comes on
before pressure in the service air tank falls below _______PSI
a. 40
b. 60
c. 80
5. If your truck or bus has dual parking control valves you can use pressure
from a separate tank
a. To balance the service brake system when you are parked
b. To stay parked twice as long without using up service air pressure
c. To release the emergency/spring/parking brakes to move a short
distance
6. The brake pedal in a air brake system
a. Controls the speed of the air compressor
b. Controls the air pressure applied to put on the brakes
c. Is connected to slack adjusters by a series of rods and linkages
7. To check the free play of manual slack adjusters of S-Cam brakes, you should
a. Park on level ground and apply the parking brakes
b. Park on a slight grade, release the parking brakes
c. Park on level ground, chock the wheels, release the parking brakes
and pull on the slack adjusters
8. Parking or emergency brakes on trucks or buses can be legally held on by
______ Pressure.
a. Spring
b. Fluid
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c. Air
9. Emergency stab braking is when you
a. Press hard on the brake pedal and apply full pressure on the hand valve
until you stop
b. Use light steady pressure on the brake pedal
c. Brake as hard as you can, then release the brakes when the wheels
lock up and put on the brakes again when the wheels start rolling
10. The most common type of foundation brake found on heavy vehicles is the
a. Wedge drum
b. Disc Brake
c. S-Cam
11. If your truck has dual air brake system and one of the systems is low on
pressure.
a. The manual slack adjusters on S-Cam brakes are not set properly
b. The brake drums will not be fully operational
c. Either the front or rear brakes will not be fully functional
12. The most important thing to do when a low-pressure warning light comes on
is to.
a. Up shift
b. Down shift
c. Stop and safely park as soon as possible
13. With air brake equipped vehicles, the parking brakes should be used
a. As little as possible
b. Any time the vehicle is parked
c. To hold your speed when going down hill
14. The air compressor governor controls
a. When air is pumped into the tanks
b. The speed of the air compressor
c. Air pressure applied to the brakes
15. The stop light switch
a. Turns on the brake light to warn other drivers behind you
b. Tells you when you need to use your emergency brakes
c. Tells you when the air brake system is low on air pressure
16. For air brake systems in good condition the air compressor should start
pumping at about _____ PSI
a. 100
b. 125
c. 150
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