DGT Vehicle Operation & Maintenance 3 — Questions and Answers
Question 1: What is the recommended action if your vehicle begins to overheat while driving?
- Turn on the heater and pull over safely (Correct answer)
- Turn off the engine immediately while moving
- Add cold water to the radiator right away
- Continue driving at reduced speed to a service station
Correct answer: Turn on the heater and pull over safely
Turning on the heater draws heat away from the engine, and pulling over safely prevents further damage from continued driving.
Question 2: What does 'tire rotation' accomplish?
- Balances tire weight distribution
- Moves tires to different positions to even out wear (Correct answer)
- Aligns the wheels properly
- Increases tire pressure uniformly
Correct answer: Moves tires to different positions to even out wear
Tire rotation moves tires between axle positions to equalize tread wear, extending the life of all four tires.
Question 3: What is the function of the vehicle's serpentine belt?
- Connects the engine to the transmission
- Drives multiple accessories like the alternator, power steering pump, and AC compressor (Correct answer)
- Controls the timing of engine valves
- Regulates fuel injection timing
Correct answer: Drives multiple accessories like the alternator, power steering pump, and AC compressor
The serpentine belt drives multiple engine accessories simultaneously, including the alternator, power steering pump, and air conditioning compressor.
Question 4: How do you know when your vehicle's coolant needs to be flushed?
- When the coolant light turns on
- According to manufacturer schedule, typically every 30,000–50,000 miles (Correct answer)
- Only when the engine overheats
- When the coolant turns bright green
Correct answer: According to manufacturer schedule, typically every 30,000–50,000 miles
Manufacturers typically recommend flushing coolant every 30,000–50,000 miles as it degrades over time, losing its anti-corrosion and freezing-point-depression properties.
Question 5: What happens if you drive with a broken or missing gas cap?
- Fuel evaporates and the check engine light may illuminate (Correct answer)
- The fuel pump works harder and fails sooner
- Water enters the fuel tank causing damage
- The fuel gauge becomes inaccurate
Correct answer: Fuel evaporates and the check engine light may illuminate
A missing gas cap allows fuel vapors to escape the tank, reducing fuel efficiency and often triggering the check engine light due to EVAP system failure.
Question 6: At what tread depth should tires be replaced for safety?
- 4/32 of an inch
- 2/32 of an inch (the legal minimum) (Correct answer)
- 6/32 of an inch
- 1/16 of an inch
Correct answer: 2/32 of an inch (the legal minimum)
Tires must be replaced when tread depth reaches 2/32 of an inch, which is the legal minimum and the point where wet-road traction becomes dangerously compromised.
Question 7: What does the 'P' position on an automatic transmission gear selector do?
- Prevents the vehicle from rolling by locking the drivetrain (Correct answer)
- Puts the vehicle in a lower gear for engine braking
- Allows the vehicle to coast freely
- Activates the parking brake automatically
Correct answer: Prevents the vehicle from rolling by locking the drivetrain
Park (P) locks the output shaft of the transmission, preventing the vehicle from rolling, but should always be used with the parking brake.
DGT Vehicle Operation & Maintenance 3
What is the recommended action if your vehicle begins to overheat while driving?