Before changing lanes, what should you do to spot a car just about to pass you?

Making a head check by turning your head is the most effective way to spot a car that is about to pass you. While mirrors provide a helpful view of your surroundings, they have blind spots that can hide vehicles, especially those that are moving quickly. A head check allows you to physically turn your head and look over your shoulder to confirm that your blind spots are clear before you change lanes. This practice enhances your awareness of your immediate surroundings and helps ensure that you can safely execute the lane change without colliding with another vehicle.

Using mirrors alone may not give you the full picture of what's happening beside you, as they can miss objects that are directly in your blind spot. Honking your horn is not a reliable method to ensure safety or visibility as other drivers may not respond appropriately. Speeding up to check only increases risk and should never be used as a strategy; it could lead to dangerous situations if you misjudge the speed of approaching vehicles. Therefore, performing a head check is the most advisable and safest method to identify any cars that might be right next to you as you prepare to change lanes.