ASE Electrical/Electronic Systems 2 — Questions and Answers
Question 1: A voltage drop test across a closed switch reads 1.2 volts. What does this indicate?
- Excessive resistance in the switch contacts (Correct answer)
- Normal operation
- An open circuit
- A short to ground
Correct answer: Excessive resistance in the switch contacts
A voltage drop greater than about 0.1V across a closed switch indicates unwanted resistance from corroded or burnt contacts.
Question 2: Which instrument is best for measuring parasitic (key-off) battery drain?
- Ammeter in series with the disconnected battery cable (Correct answer)
- Voltmeter across the battery posts
- Ohmmeter on the alternator
- Test light on the fuse box
Correct answer: Ammeter in series with the disconnected battery cable
An ammeter placed in series in the battery circuit measures the actual current drawn while the vehicle is off.
Question 3: A relay has terminals 85, 86, 87, and 30. Which two terminals are the control (coil) side?
- 85 and 86 (Correct answer)
- 30 and 87
- 87 and 87a
- 30 and 86
Correct answer: 85 and 86
Terminals 85 and 86 energize the relay coil, while 30 and 87 carry the switched load.
Question 4: Total resistance in a parallel circuit is always:
- Less than the smallest individual resistor (Correct answer)
- Equal to the sum of all resistors
- Greater than the largest resistor
- Equal to the average of the resistors
Correct answer: Less than the smallest individual resistor
Adding parallel paths gives current more routes, lowering total resistance below the smallest branch.
Question 5: An alternator's diodes are responsible for:
- Converting AC voltage to DC (Correct answer)
- Regulating field current
- Stepping up voltage
- Storing reserve charge
Correct answer: Converting AC voltage to DC
The diode rectifier bridge converts the stator's alternating current into direct current for the vehicle.
Question 6: A technician finds 12.6 volts at rest and 14.2 volts with the engine running. This indicates:
- A properly charging system (Correct answer)
- An overcharging alternator
- A dead battery cell
- An open field winding
Correct answer: A properly charging system
Charging voltage in the 13.5–14.7V range with a full 12.6V resting battery indicates normal charging.
Question 7: Which condition would cause a continuously blown fuse immediately after replacement?
- A direct short to ground in the circuit (Correct answer)
- High resistance in a connector
- An open ground
- A weak battery
Correct answer: A direct short to ground in the circuit
A dead short to ground creates excessive current that instantly blows the fuse again.
ASE Electrical/Electronic Systems 2
A voltage drop test across a closed switch reads 1.2 volts.
What does this indicate?