CDL Combination Vehicles TestDriving Combination Vehicles SafelyMedium
A commercial driver is operating a combination vehicle on a four-lane interstate highway with moderate traffic. The driver needs to change lanes from the right lane to the left lane. What is the most critical step the driver must perform immediately after checking mirrors and signaling, but before initiating the lane change?
- AActivate the hazard lights to alert other drivers of the imminent lane change.
- BAccelerate rapidly to quickly move into the new lane.
- CBriefly apply the service brakes to slow down and create a gap.
- DCheck blind spots by turning their head to confirm no vehicles are present.
Show answer & explanationAnswer & explanation
Correct answer: D. Check blind spots by turning their head to confirm no vehicles are present.
Combination vehicles have large blind spots, especially along their sides. After checking mirrors, a head check is essential to visually confirm that no vehicles are hidden in these areas before starting the lane change.
Why the other options are wrong
- A. Hazard lights are typically for disabled vehicles or extreme hazards, not for routine lane changes, and can cause confusion.
- B. Rapid acceleration during a lane change can be dangerous and reduces control, especially with a combination vehicle.
- C. Braking before a lane change can be unexpected by other drivers and may cause a rear-end collision.
Combination Vehicle Blind Spots
Combination vehicles have significant blind spots (no-zones) around all four sides that mirrors cannot fully cover. A head check is essential before any lateral movement.
- Blind spots are larger than passenger vehicles.
- Mirrors do not show all areas.
- Head checks are critical for safety.
Memory trick: Mirror, Signal, Head Check, Go Slow.