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Chapter 10
End of Chapter Review Questions Answer Key
1. When an incandescent light bulb is energized in an electrical circuit, what is electrical
energy converted to?
2. What is the function of a headlamp dimmer switch?
3. What type of headlight fires an arc through gas to produce light energy?
4. Which of the following best explains the construction of a halogen headlamp
element?
5. How much voltage is required to sustain the arc in a typical HID headlamp assembly?
6. Which of the following best defines light energy?
7. Which of the following would be used to switch turnlights on a truck chassis?
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8. How many contacts are in a typical tractor-to-trailer electrical connector?
9. What color code is used for the brake light circuit in a truck trailer electrical
connector?
10. 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?
11. Which of the following governs highway truck exterior lighting standards in North
American trucks?
12. In a standard SAE relay, which of the following is normally open (NO)?
13. In an older standard SAE relay, which pair of terminals energizes the coil circuit?
14. 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?
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15. 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?
16. What is the maximum acceptable total voltage drop across all of the terminals and
cables on the insulated side of a cranking circuit?
17. 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?
18. 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?
19. What type of filament is used in a halogen headlight?
20. 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?