Understanding Automotive Electrical Systems

Which of the following is a function of a fuse in an automotive electrical circuit?

• To store electrical energy

• To protect the circuit from overcurrent

• To convert AC to DC

• To increase voltage

What is the unit of electrical resistance?

• Ampere

• Ohm

• Volt

• Watt

• 2A

• 3A

• 4A

• 6A

Which symbol in a wiring diagram typically represents a ground connection?

• A zigzag line

• A triangle pointing downward with horizontal lines

• A circle with a plus sign

• Two parallel lines

A headlight circuit is not working. Which of the following is the first step you should take to troubleshoot the problem?

• Replace the headlight bulb

• Check the fuse for the headlight circuit

• Replace the battery

• Disconnect the alternator

If a wire in a car’s electrical system is too thin for the current it carries, what is the most likely result?

• The wire will increase the voltage

• The wire may overheat and cause a fire

• The wire will store more energy

• The wire will decrease resistance

• 0.5A

• 1A

• 2A

• 4A

You are given a wiring diagram showing a battery, a switch, and a lamp connected in series. If the lamp does not light up when the switch is closed, which of the following could be a possible cause?

• The battery is fully charged

• The switch is open

• The lamp is burned out

• The wires are properly connected

A car’s tail lights are dimmer than usual. Using a wiring diagram, you find that the ground connection is corroded. Explain how this could cause the problem and suggest a solution.

• The corroded ground increases resistance, reducing current to the tail lights; cleaning or replacing the ground connection will restore normal brightness.

• The corroded ground increases voltage, making the lights dim; replacing the battery will fix it.

• The corroded ground decreases resistance, causing the lights to dim; adding more bulbs will help.

• The corroded ground has no effect; the problem is with the alternator.

A technician measures 0 volts across a fuse in a live circuit, but the circuit is not working. Using strategic troubleshooting, what should the technician check next?

• Replace the fuse immediately

• Check for an open circuit or broken wire upstream of the fuse

• Replace the battery

• Install a larger fuse