Deck 10: Chassis Electrical Circuits

Question 1

Most instrument panel display gauges are designed to display normal values in which areas of a circular display?

A) 12 to 4 o'clock
B) 10 to 2 o'clock
C) 3 to 9 o'clock
D) 4 to 8 o'clock

Answer 1

B

Question 2

What is the maximum brightness permitted in headlamps by current legislation?

A) 55,000 candle power
B) 75,000 candle power
C) 150,000 candle power
D) 200,000 candle power

Answer 2

D

Question 3

When selecting solder to splice copper wire,which would be correct?

A) silver solder
B) rosin core
C) acid core
D) pure lead solder

Answer 3

B

Question 4

Where would you most likely find fluorescent lights on a truck?

A) not used on vehicles
B) headlights
C) marker lights
D) sleeper and bunk lights

Question 5

What is the function of a pyrometer?

A) records chassis service hours
B) measures exhaust gas temperature
C) displays engine speed
D) indicates boost pressure

Question 6

When an ATA standard seven-wire trailer cord is properly connected,what color wire is used for the trailer brake lights?

A) white
B) blue
C) red
D) black

Question 7

What is visible light known as?

A) electrons
B) protons
C) photons
D) neutrons

Question 8

What color used to illuminate dash instrument displays is said to assist driver night vision?

A) white
B) blue
C) green
D) red

Question 9

What does the brown color code represent in a SAE/ATA standard 7-wire trailer connector cord?

A) auxiliary
B) brakes
C) ground
D) tail and license plate lights

Question 10

When a truck has a data bus network,what type of switch can be used to replace an electro-mechanical switch?

A) pilot switch
B) toggle switch
C) smart switch
D) latching switch

Question 11

Technician A says that halogen lamps produce more light per unit of energy consumed with the result that they are more efficient.Technician B says that halogen lamps run at much higher temperatures than comparable incandescent bulbs.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 12

In a typical incandescent bulb,what is the filament surrounded by?

A) pure oxygen
B) pure nitrogen
C) inert gas
D) vacuum

Question 13

What is the function of a tachometer?

A) measures engine rpm
B) measures road speed
C) displays engine hours
D) displays exhaust gas temperature

Question 14

In a typical truck,four horizontal headlight system where would the double filament headlamps be located?

A) both on inside
B) both on outside
C) one on driver outside,one on curbside inside
D) one on driver inside,one on curbside outside

Question 15

When adjusting headlights without the aid of a headlight aiming device,what should be the distance between the front of the truck and the target screen?

A) 10 feet
B) 25 feet
C) 50 feet
D) 100 feet

Question 16

What federal legislation limits the maximum brightness of truck headlamps?

A) FMVSS 101
B) FMVSS 104
C) FMVSS 108
D) FMVSS 121

Question 17

What is the function of an odometer?

A) measures distance travelled
B) displays temperature values
C) measures road speed
D) displays current consumed

Question 18

What maximum temperatures do the tungsten filaments in incandescent bulbs heat to in normal operation?

A) 110 degrees Fahrenheit
B) 1500 degrees Fahrenheit
C) 2500 degrees Fahrenheit
D) over 4000 degrees Fahrenheit

Question 19

Technician A says that when replacing a tungsten lightbulb element,you should avoid touching the bulb with your bare hands.Technician B says that halogen headlights produce about twice as much brightness measure in candle power as incandescent headlights.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 20

What is used to ignite the arc in a florescent light?

A) spark
B) heating element
C) ballast resistor
D) terminating resistor

Question 21

When attempting to diagnose instrument cluster unit (ICU)malfunctions what should you do first?

A) replace the module
B) use a testlight to locate the problem
C) use a DMM to locate the problem
D) access the data bus for DTCs

Question 22

Which of the following types of vehicle lamp is likely to function for the longest period?

A) incandescent
B) halogen
C) LED
D) HID

Question 23

What is the highest distance above the road level an HID headlamp can be positioned on the front of a truck?

A) 24 inches
B) 33.5 inches
C) 37.5 inches
D) 40 inches

Question 24

Which of the following can significantly increase the life of all vehicle light systems?

A) chassis voltage stabilizer
B) increasing voltage regulator setting
C) limiting alternator maximum speed
D) replace at each PMI

Question 25

How much voltage is required to ignite the arc of a HID headlamp?

A) 20,000 volts
B) 85 volts
C) 12 volts
D) 5 volts

Question 26

Technician A says that HID headlamps convert about 80% of the electrical energy they consume into light energy.Technician B says that halogen lights use more energy but produce a 20% brighter beam than equivalent HID beams.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 27

When soldering copper wire in medium gauge truck electrical circuits,what should be used to produce the heat?

A) use cold melt solder only
B) 100 watt soldering gun
C) 500 watt soldering iron
D) propane torch

Question 28

After the arc has been ignited in a Xenon light,how much voltage is required to maintain it?

A) 20,000 volts
B) 85 volts
C) 12 volts
D) 5 volts

Question 29

The technology that superimposes dash display data onto the windshield within the driver's line of sight is known as:

A) DVD
B) HUD
C) HID
D) LED

Question 30

What is another name for a high intensity discharge (HID)headlamp?

A) tungsten lamp
B) halogen lamp
C) neon lamp
D) xenon lamp

Question 31

A driver complains that his trailer marker lights continually cycle on-and-off,being illuminated for a couple of minutes,then quit for up to five minutes.What type of circuit protection device is likely installed in the trailer marker light circuit?

A) blade type fuse
B) ballast resistor
C) SAE #1 circuit breaker
D) SAE #2 circuit breaker

Question 32

Why are LED light systems a major advantage on trailers equipped with ABS brakes?

A) power for LED is sourced from ABS
B) the PLC multiplex routes through LED circuit
C) ABS logic controls LED light circuit
D) LEDs require little power leaving more for the ABS during panic stops

Question 33

What produces the light emitted by a xenon headlamp?

A) tungsten filament
B) halogen filament
C) arc ignited across inert gas
D) infrared gas

Question 34

If a steering column mounted stalk switch uses 'smart' technology,what does it produce to signal status changes?

A) direct electro-mechanical signals
B) sends command signals to a control module
C) energizes dedicated hard wire circuits
D) grounds-out live wires

Question 35

Which medium do night visioning electronic systems such as Bendix XVision use to produce imaging?

A) doppler radar
B) infra-red
C) ultra-violet
D) microwave

Question 36

Which American Trucking Association,Technology and Maintenance Council (TMC)recommended practice (RP)outlines the placement of instrument cluster gauges?

A) RP 401
B) RP 285
C) RP 121
D) RP 108

Question 37

Technician A says that HID headlamps frequently fail because they are more vulnerable to road shock and vibration than halogen filament lamps.Technician B says that when HID headlamps fail,it is usually due to frequent cycling.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 38

If a driver has 20/20 vision,how well is it estimated that the driver can see under night driving conditions?

A) 20/20
B) 20/30
C) 20/40
D) 20/50

Question 39

When comparing the safety of LEDs versus incandescent lamps used as brake lights,which of the following is correct?

A) LEDs require more maintenance
B) cost of LEDs is greater over lifetime of chassis
C) LEDs illuminate more rapidly
D) LED tail lights consume more current

Question 40

What is the main cause of HID headlamp failures?

A) burned out filaments
B) vibration of lamp assembly
C) oxidation of electrodes
D) loss of inert gas

Question 41

When assessing chassis electrical system performance,where should you always begin?

A) batteries
B) alternator
C) cranking motor
D) power distribution module

Question 42

On a standard SAE relay,which two terminals are used to energize the coil or control circuit?

A) 1 and 2
B) 2 and 3
C) 3 and 4
D) 4 and 5

Question 43

Which of the following circuit protection devices tend to be most commonly used in truck chassis electrical circuits?

A) blade fuses
B) solid state
C) cycling circuit breakers
D) non-cycling circuit breakers

Question 44

When the control coil is energized in a standard SAE relay,which of the following relay circuits is switched to closed status?

A) 1 - 2 (86 - 85)
B) 2 - 3 (85 - 30)
C) 3 - 4 (30 - 87a)
D) 3 - 5 (30 - 87)

Question 45

Technician A says that the typical current draw of headlamps is around 10 amps.Technician B says that headlamp resistance should measure approximately 10 ohms in a properly functioning headlamp.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 46

On a standard SAE relay,which terminal should be the common terminal?

A) 1 (86)
B) 2 (85)
C) 3 (30)
D) 5 (87)

Question 47

Technician A says that a properly functioning LED light should produce mosty light energy from the electrical energy it consumes.Technician B says that light systems that produce the least amount of heat are the most efficient.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 48

Technician A says that voltage drop is the effective measurement of resistance in a circuit.Technician B says that voltage drop is a less effective means of locating high resistances in a circuit than measuring resistance with an ohmmeter.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 49

What should you do to enable a non-cycling circuit breaker to close again after it has tripped and opened?

A) replace it
B) key off the ignition circuit to cool the breaker
C) short it through with a jumper wire
D) use aluminum foil to close terminals

Question 50

With a truck ignition key-off and all electrical loads off,you disconnect the main ground battery cable and connect a test light in series with the battery ground clamp and the battery ground post.The test light illuminates and remains illuminated.What is the likely problem?

A) Nothing
B) Possible battery drain
C) High resistance in the ground circuit
D) Imminent battery failure