What is the correct sequence for checking mirrors and blind spots before changing lanes?

• A. Check rearview and side mirrors, signal, then check over your shoulder for the blind spot before moving.
• B. Signal, then check mirrors, then shoulder check, then move.
• C. Check blind spots only after moving.
• D. Check mirrors after you start the lane change.

Answer: (A)

Before changing lanes, you want a clear, reliable picture of your surroundings. Start by checking the mirrors so you can see traffic behind and beside you. Then signal early to let other drivers know you intend to move. After signaling, perform a shoulder check to look over the lane you want to enter and confirm there’s no vehicle in your blind spot. Move only when the space is clear and it’s safe.

If you skip the shoulder check or try to signal before you’ve scanned for traffic, you’re increased risk of a collision or confusing other drivers. Checking blind spots after you begin the lane change is dangerous because you may already be too close to another vehicle. Likewise, waiting to check mirrors until after you’ve started to move means you don’t have a full view of traffic before committing to the lane change.