310S Electrical and Electronic Systems 5

Question 1

What is the function of the throttle position sensor (TPS)?

Accepted Answer

To signal the ECM the angle and rate of change of the throttle plate opening

Answer

To control the idle air bypass valve

Answer

To measure the air temperature entering the throttle body

Answer

To regulate fuel pressure at the fuel rail

Question 2

A multiplexed vehicle has total communication failure. Neither the scan tool nor any module responds. What should the technician check first?

Accepted Answer

The CAN bus terminating resistors and bus wiring for opens or shorts

Answer

All individual module fuses

Answer

The battery state of charge

Answer

The OBD-II connector for bent pins

Question 3

What is the purpose of the starter motor overrunning clutch (Bendix drive)?

Accepted Answer

To disengage the starter drive from the flywheel after the engine starts

Answer

To increase the torque of the starter motor

Answer

To reduce electrical current draw during cranking

Answer

To cushion the starter motor mounting

Question 4

A scan tool shows long-term fuel trim (LTFT) at +25%. What does this indicate?

Accepted Answer

The ECM is adding 25% more fuel than the base fuel map to maintain stoichiometric ratio

Answer

The engine is running 25% rich

Answer

The fuel injectors are oversized by 25%

Answer

The fuel pressure is 25% above specification

Question 5

What is the purpose of the immobilizer system in a modern vehicle?

Accepted Answer

To disable the fuel and/or ignition system unless the correct transponder key is detected

Answer

To prevent the vehicle from being towed

Answer

To lock the steering wheel when the key is removed

Answer

To activate the alarm horn when the door is opened

Question 6

When measuring resistance of a component, why must the circuit be de-energized?

Accepted Answer

To prevent the external voltage from causing inaccurate readings and potentially damaging the ohmmeter

Answer

To protect the technician from electrical shock

Answer

To reset the component to its default state

Answer

To allow the multimeter to switch to resistance mode