Deck 4: Electrical Components

Question 1

RTV silicone sealer should be applied to a wire repair to seal out water.

Answer 1

False

Question 2

All types of wire with identical gauge numbers (e.g. 12 AWG) always have the same thickness of insulation material.

Answer 2

False

Question 3

12V is measured across a switch in a 12V electric circuit. This indicates the switch must be closed (in the ON position).

Answer 3

False

Question 4

The common terminal of an ISO relay (terminal 30) is always connected to chassis ground.

Question 5

A technician measures an open circuit (infinite resistance) between an ISO relay normally-open terminal 87 and the normally-closed terminal 87A. This indicates the relay should be fully-functional.

Question 6

Relay coil suppression prevents the relay from drawing too much current.

Question 7

A relay can be felt and heard to "click" when energized. This indicates the relay is fully functional.

Question 8

Referring to figure shown below, the left side back-up lamp is very dim but the right side back-up lamp is bright when the transmission is in reverse. The back-up lamp switch is not the likely cause of the dim left side back-up lamp.

Question 9

Which wire would have the largest diameter conductor?

A) 20 AWG
B) 0 AWG
C) 4-0 AWG (0000 AWG)
D) 0.5 mm²

Question 10

Technician A says that 10 feet (3 m) of 10 AWG wire has less resistance than 20 feet (6 m) of 10 AWG wire. Technician B says that 10 feet (3 m) of 10 AWG wire has more resistance than 10 feet (3 m) of 20 AWG wire. Who is correct?

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

Question 11

A momentary-contact normally-open switch would likely be used to control which type of device?

A) Horn
B) Tail lamps
C) Interior lamp
D) Blower motor

Question 12

Technician A says that a normally-closed switch is always closed when all conditions are normal. Technician B says that a normally-open switch is always open when all conditions are normal. Who is correct?

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

Question 13

Which is the following is an electrical load?

A) Headlamp
B) Blower motor
C) Resistor
D) All of the above could be considered as an electrical load.

Question 14

Technician A says that the primary purpose of a circuit protection device is to protect the electrical load, such as a headlamp. Technician B says that it is ok to use a larger fuse if the existing fuse keeps blowing. Who is correct?

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

Question 15

Which of the following is a true statement?

A) Inrush current refers to a high level of current that is drawn by some devices when first switched on.
B) A 10A fuse will always immediately blow when a current of more than 10A flows through the fuse.
C) Doubling the current flow always causes the power dissipated (wattage) to also double.
D) All of the above are true statements.

Question 16

A technician measures a circuit resistance with an ohmmeter and finds 1 ohm of resistance. He then connects a 12V battery to the circuit and measures a current of 1A. Per Ohm's law, he expected 12A of current to flow. What is a likely reason for the discrepancy?

A) Ohm's law is only a theory.
B) Positive temperature coefficient of the load
C) Lenz law
D) The circuit was shorted to ground when the resistance measurement was obtained.

Question 17

Technician A says that a headlamp that does not illuminate due to high circuit resistance would be described as a "short". Technician B says that a blown fuse or tripped circuit breaker is always caused by a short to ground. Who is correct?

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

Question 18

Referring to the figure shown below, a blown fuse F5 would likely be caused by which of the following?

A) An open circuit between the fuse and the mirror heat switch
B) A disconnected ground terminal for the mirror heating elements
C) Too large of a MEGA fuse supplying fuse F5
D) A short to ground somewhere in the wiring harness between the fuse and the loads

Question 19

Referring to the following figure, the mirror heat does not function on either side of the truck, but the back-up lamps illuminate with the transmission in reverse. Which is the least likely cause of the inoperative mirror heat?

A) Both of the mirror heat ground circuits are open.
B) The mirror heat switch is defective.
C) There is an open circuit between the fuse and the mirror heat switch.
D) There is an open circuit between the switch and the splice in the wiring harness where the left and right side mirror heat circuits separate.

Question 20

The three types of shorted circuits include a short to ground, a short to battery positive, and _______?

A) an open short
B) a short to the frame
C) a wire-to-wire short
D) a positive temperature coefficient short