NAPA Electrical and Electronic Systems 2

Question 1

During cranking, a voltage drop greater than about how much across the battery positive cable to the starter indicates excessive resistance?

Accepted Answer

0.5 V

Answer

Most manufacturers allow roughly 0.5 V maximum drop across the starter feed cable under cranking load.

Question 2

What is a generally acceptable maximum parasitic (key-off) battery drain on most late-model vehicles after modules go to sleep?

Accepted Answer

About 50 mA

Answer

Most vehicles should draw roughly 50 mA or less once all modules have entered sleep mode.

Question 3

To measure current flow in a circuit with a digital multimeter, how must the meter be connected?

Accepted Answer

In series with the circuit

Answer

An ammeter must be placed in series so all circuit current flows through it.

Question 4

A DMM set to ohms reads 'OL' when connected across a wire. What does this indicate?

Accepted Answer

An open circuit

Answer

OL means the resistance is beyond the meter's range, which indicates an open circuit.

Question 5

Under load, a good ground-side connection should typically show a voltage drop of no more than about:

Accepted Answer

0.1 V

Answer

Ground circuits should drop about 0.1 V or less; more indicates resistance.

NAPA - National Automotive Parts Association Certified Mechanic Practice Test