NOCTI Automotive Technology 3

Question 1

What is the standard operating voltage of a fully charged 12-volt automotive battery?

Accepted Answer

12.6 volts

Answer

A fully charged 12-volt lead-acid battery at rest (surface charge dissipated) reads approximately 12.6 volts open circuit voltage.

Question 2

What is the primary function of the alternator in an automotive electrical system?

Accepted Answer

Convert engine mechanical energy into electrical energy to charge the battery and power accessories

Answer

The alternator is driven by the engine and uses electromagnetic induction to produce AC electricity, which is rectified to DC to recharge the battery and power vehicle systems.

Question 3

Which type of fuel injection delivers fuel directly into the combustion chamber rather than the intake port?

Accepted Answer

Gasoline direct injection (GDI)

Answer

Gasoline Direct Injection (GDI) sprays fuel directly into the combustion chamber at high pressure, improving fuel efficiency and power output.

Question 4

While driving, the battery warning light illuminates on the dashboard. What is the MOST likely cause?

Accepted Answer

Alternator is not charging the battery

Answer

The battery warning light typically indicates the charging system is not producing adequate voltage, most often due to a failing alternator, broken belt, or voltage regulator fault.

Question 5

What is the function of the Throttle Position Sensor (TPS)?

Accepted Answer

Signal the ECM about throttle plate angle to calculate engine load and fuel demand

Answer

The TPS sends a voltage signal corresponding to throttle plate position to the ECM, which uses it to determine engine load and adjust fuel injection and ignition timing.

NOCTI - National Occupational Competency Testing Institute Practice Test

NOCTI - National Occupational Competency Testing Institute Practice Test

NOCTI Automotive Technology 3