cp. 24 Wheel ends
cp.29 foundations
cp.30 air brakes
cp. 31 air diagnosis
cp. 32 ABS systems
100
wheel seal leaks
What is one of the largest maintenance concerns for commercial vehicle operators and fleets alike.
100
components located at the wheel ends are referenced as ********** brakes.
What are foundation
100
The two main functions of a brake chamber.
What is emergency "spring" brakes and "service" brakes.
100
What has an angle of 90 degrees with a 80-100 p.s.i. brake application pressure.
What is the brake chamber push rods orientation to the slack adjuster when brakes are properly adjusted.
100
what does "RSC" or "DSC" or "CAS" or "ABS" stand for? must have two correct.
What is "roll stability control" "Collision avoidance systems" "Directional stability Control" "Anti-lock Brake Systems"
200
the common torque value for a bearing retaining nut?
What is 250-300 foot pounds or 339-407 newton meters
200
technicians say early air disk brakes had what issues? list at least 2.
What is maintenance issues, operational issues, lack of parts availability, higher than drum brake corrosion, undersized rotors
200
The air pressure in P.S.I. required to actuate emergency braking at the wheel ends.
What is zero. The exhausting or eve loss of "hold off" air causes the "power spring" to actuate emergency or park brakes in a brake actuator.
200
ABS modulator valve operation can be checked during a key on cycle. it is called the ***** test.
What is 'CHUFF" *the sound made during the valves operation. **modulator valves can also be checked by using an ohmmeter to check resistance but, should never be done without also doing a "chuff"test that physically operates the valve.
200
Tech A says the amber trailer ABS light will come on for several seconds and go off after the ignition is switched on and the system detects no faults. Tech B says wheel slips or uneven wheel speeds prevent proper forward motion and can cause loss of directional stability. Who is correct?
What is both are correct
300
on spoke wheels, lateral runout does NOT need to be checked but the fastener tightening pattern needs to be in a _______ pattern.
What is a circular pattern
300
types of brake fade-list 4
What is mechanical,chemical,heat,water,glazing of lining
300
used to prevent the simultaneous application of two forces in the brake system at the same time.
What is an "anti-compounding valve"
300
air brake imbalance occurs when,
What is some brake valves or chambers receive air faster than others.
300
When ABS was first introduced, what wire in the trailer connector supplies dedicated power "current" to the trailer ABS system? wire color and terminal position number.
What is #7 BLUE
400
more are used on "HUB PILOTED" wheel?
What is wheel studs and lug nuts
400
friction blocks are riveted why?
What is to increase the structural\mechanical bond to the shoe plate. *also-riveted shoes are generally considered superior to non- riveted shoes.
400
the spring brake relay valve is what type of valve? or whats another basic name for the spring brake relay valve.
What is an inversion valve
400
air reservoirs with automatic drain valves should be purged every 2 years or 24.000 miles true or false?
What is False. "automatic" drain valves perform self purging every time tank internal pressure drops more than 50 p.s.i.
400
ABS wheel speed is averaged by the ABS control module and broadcasts that information over the J-1939 data network. DO automatic traction control systems also use this data and share a network connection? yes or no?
What is yes. both the ABS module and ATC communicate on the same network and share information. many vehicle systems use wheel speed data.
500
locks the adjustment in place as well as, adjusts the bearing end play.
What is a wheel end retaining nut. "nut" only- not acceptable...
500
the thickness of a brake friction "block"
What is 3/4 of an inch
500
which is correct concerning air valves featuring pressure compensation balance? A-air pressure to brake chambers is held constant when inlet pressures and delivery pressures are equal. B-the pressure compensating balance feature of air valves ensures a consistent delivery of air pressure if theirs a leak in the delivery lines or brake chambers
What is both are correct.
500
excessive water in air reservoirs are caused by answer at least three.
What is cracked air compressor head, bad comp. head gasket,malfunctioning air dryer purge valve, malfunctioning air dryer heater.
500
Tech A says, abs modulator valves are high capacity on\off valves that contain solenoids used to control air brake application pressure. Tech B says, these two "inlet-air" and "exhaust-air" solenoids are energized and de-energized by electrical signals from the ABS ECU to allow the controller to "pump" or "apply" the brakes. Whos correct?
What is both tech A and B. modulator valves can both apply air to actuate brakes and exhaust air to release brakes.
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