AIR BRAKES

Question 1

WHAT IS THE BEST WAY TO TEST YOUR VEHICLES LOW AIR PRESSURE WARNING SIGNAL?

Answer 1

STEP ON AND OFF THE BRAKE PEDAL, WITH THE ENGINE OFF, TO REDUCE AIR PRESSURE BELOW 60 PSI

Question 2

WHICH OF THE FOLLOWING IS TRUE ABOUT YOUR BRAKE FUNCTION IF YOUR ABS FAILS?

Answer 2

YOU WILL STILL HAVE NORMAL BRAKE FUNCTION, AND SIMPLY NEED TO GET THE ABS REPAIRED SOON

Question 3

THE PURPOSE OF A SUPPLY PRESSURE GAUGE IS:

Answer 3

TO TELL YOU HOW MUCH AIR IS IN THE TANK

Question 4

WHICH OF THE FOLLOWING SHOULD YOU DO BEFORE LEAVING YOUR VEHICLE UNATTENDED?

Answer 4

• PUT ON THE PARKING BRAKES
• CHOCK THE WHEELS
• REMOVE THE KEYS

Question 5

WHEN SHOULD YOU DRAIN YOUR AIR TANKS?

Answer 5

AT THE END OF EACH WORKING DAY

Question 6

THE TRACTOR PROTECTION VALVE:

Answer 6

• WILL CLOSE ITSELF AUTOMATICALLY IF THE AIR SUPPLY DROPS TO A CERTAIN LEVEL
• PROVIDES YOUR AIR SUPPLY FOR BRAKE SYSTEM
• IS CLOSED BY THE PARKING BRAKES

Question 7

WHICH OF THE FOLLOWING IS A REASON THAT AIR TANKS MUST BE DRAINED?

Answer 7

YOUR BAKES MAY FAIL DUE TO THE WATER FREEZING

Question 8

HOW DO BRAKES WORK ON LONG, STEEP DOWNGRADE?

Answer 8

AS A SUPPLEMENT TO THE BRAKING EFFECT ON YOUR ENGINE

Question 9

GENERALLY, WHY MUST YOU TAKE AN EXAM ABOUT AIR BRAKES?

Answer 9

OTHERWISE, YOU WOULD HAVE A CDL WITH RESTRICTIONS

Question 10

THE MAXIMUM LEAKAGE RATES PER MINUTE ARE:

Answer 10

3 PSI FOR SINGLES, 4 PSI FOR COMBINATION VEHICLES

Question 11

WHICH OF THE FOLLOWING IS NOT PART OF THE BRAKING PROCESS WHEN DRIVING A TRACTOR-TRAILER COMBINATION VEHICLE WITH ABS?

Answer 11

YOU SHOULD DRIVE MORE QUICKLY SO THAT YOU WILL BE ABLE TO KEEP THE TRAILER AND TRACTOR STRAIGHT

Question 12

SPRING BRAKES ARE:

Answer 12

• MADE UP OF POWERFUL SPRINGS, THAT ARE HELD BACK, WHILE YOU ARE DRIVING, BY AIR PRESSURE
• NOT GOING TO HAVE FULL EFFECT UNTIL YOUR PSI DROPS TO A CERTAIN RANGE, OFTEN 20 TO 30 PSI
• BRAKES THAT COME ON AUTOMATICALLY ON A TRUCK OR A TRACTOR WHEN THE PSI DROPS TOO LOW

Question 13

WHICH OF THE FOLLOWING FACTORS CAN CAUSE BRAKES TO FAIL OR FADE

Answer 13

• BRAKES BEING OUT OF ADJUSTMENT
• NOT RELYING ON ENGINE BRAKING ENOUGH
• EXCESSIVE USE OF THE SERVICE BRAKES

Question 14

WHICH OF THE FOLLOWING IS NOT PART OF THE BRAKE SYSTEM?

Answer 14

RADIO SIGNAL SYSTEM

Question 15

AT WHAT MEASUREMENT IS THE SAFETY VALVE USUALLY SET TO OPEN?

Answer 15

150 PSI

Question 16

HOW WOULD YOU CHECK YOUR TRUCK’S SLACK ADJUSTERS?

Answer 16

USE GLOVES AND PULL HARD ON EACH SLACK ADJUSTER YOU CAN REACH

Question 17

WHICH OF THE FOLLOWING DOES ABS DO?

Answer 17

ACTIVATES WHEN THE WHEELS ARE ABOUT TO LOCK UP

Question 18

WHICH VEHICLES MUST HAVE LOW AIR PRESSURE WARNING SIGNALS?

Answer 18

ALL VEHICLES WITH AIR BRAKES CURRENTLY IN OPERATION

Question 19

SLACK ADJUSTERS ARE:

Answer 19

• PART OF YOUR AIR BRAKE SYSTEM USED TO ADJUST THE BRAKES
• BETWEEN THE POWER SCREW AND PUSH ROD ON DISC BRAKES
• BETWEEN THE PUSH ROD AND S-CAME ON DRUM BRAKES

Question 20

WHICH OF THE FOLLOWING IS NOT PART OF THE DRUM BRAKE?

Answer 20

SAFETY VALVE

Question 21

HOW CAN YOU TELL IF YOUR VEHICLE IS EQUIPPED WITH AN ANTI-LOCK BRAKING SYSTEM

Answer 21

IF THE VEHICLE IS MANUFACTURED AFTER 1998

Question 22

WHEN SHOULD YOU USE THE PARKING BRAKE?

Answer 22

EVERY TIME YOU LEAVE YOUR VEHICLE, EXCEPT FOR RARE EXCEPTIONS

Question 23

WHICH CONDITIONS ARE FRONT WHEEL BRAKES GOOD UNDER?

Answer 23

ALL WEATHER CONDITIONS

Question 24

WHICH OF THE FOLLOWING IS TRUE ABOUT A DUAL AIR BRAKE SYSTEM?

Answer 24

• THEY USE A SINGLE SET OF BRAKE CONTROLS
• ONE IS CALLED THE “PRIMARY” AND ONE IS CALLED THE “SECONDARY” SYSTEM
• ONE SYSTEM USUALLY OPERATES THE FRONT AXLE AND ONE OPERATES THE REAR AXLE

Question 25

WHAT IS THE BEST WAY TO TEST IF YOUR VEHICLE’S SPRING BRAKES COME ON AUTOMATICALLY?

Answer 25

• CONTINUE TO STEP ON AND OFF THE BRAKE PEDAL UNTIL THE MANUFACTURER’S LOW PSI SPECIFICATION HAVE BEEN MET FOR SPRING BRAKES TO DEPLOY
• CONTINUE TO STEP ON AND OFF THE BRAKE PEDAL UNTIL THE PARKING BRAKE VALVE POPS OUT ON SINGLE VEHICLES
• CONTINUE TO STEP ON AND OFF THE BRAKE PEDAL UNTIL THE PARKING VALVE POPS OUT, ON TRACTOR TRAILER VEHICLES