Lighting Boards (big boards) Flashcards
When an incandescent light bulb is energized in an electrical circuit, what is electrical energy converted to?
heat and light
What is the function of a headlamp dimmer switch?
switches headlamps between separate low-and high-beam circuits
What type of headlight fires an arc through gas to produce light energy?
HID
Which of the following best explains the construction of a halogen headlamp element?
tungsten filament encased in a quartz envelope
How much voltage is required to sustain the arc in a typical HID headlamp assembly?
around 85 volts
Which of the following best defines light energy?
a. heat b. photons c. electrons d. protons
photons
Which of the following would be used to switch turn lights on a truck chassis?
a. stalk switch b. headlamp switch c. brake pressure switch d. toggle switch
stalk switch
How many contacts are in a typical tractor-to-trailer electrical connector?
seven
What color code is used for the brake light circuit in a truck trailer electrical connector?
red
When truck and trailer clearance lights and headlamps seem to burn out at a high rate, which of the following would be a required step in troubleshooting?
a. voltage losses in ground circuit b. battery state of charge c. battery surface charge d. charging system voltage regulator
charging system voltage regulator
What governs highway truck exterior lighting standards in North American trucks?
FMVSS 108
In a standard SAE relay, which of the following is normally open (NO)?
a. 7 b. 4 c. 5 d. 3
5
In an older standard SAE relay, what pair of terminals energizes the coil circuit?
85 and 86
The headlights on a truck with electromechanical controls and circuit breaker protection continuously illuminates for a short period and then cut out. Technician A says that if the circuit breaker is a type 1, replacing it with a type 2 should repair the problem. Technician B says that the problem is likely caused by a malfunction in a type-2 circuit breaker. Who is correct?
Neither A nor B
Technician A says that on a standard SAE relay, terminal 3 is always the common terminal. Technician B says that in a standard SAE relay, the coil circuit must be energized to close the normally open 5 terminal. Who is correct?
Both A and B
What is the maximum acceptable total voltage drop across all of the terminals and cables on the insulated side of a cranking circuit?
0.5 volt
Technician A says that a corroded light unit terminal could result in an increased voltage drop across the terminal. Technician B says that a corroded light unit terminal could result in heat at the terminal. Who is correct?
Neither A nor B
Technician A says that a disadvantage of using LEDs as stoplights is that when the circuit is switched on, they illuminate at a slower speed than incandescent bulbs. Technician B says that xenon headlamps are a disadvantage in trucks because they have a shorter service life than halogen bulbs. Who is correct?
Neither A nor B
What type of filament is used in a halogen headlight?
tungsten
Technician A says that HID headlamps consume more electrical power than equivalent halogen headlamps. Technician B says that HID headlamps are brighter and their blue light is more similar to natural sunlight than that of halogen lamps. Who is correct?
Technician B only
