What is one of the first things to do in checking a vehicle before a trip?

Performing a full pre-trip inspection is essential because it ensures the vehicle is safe and ready for travel. This inspection involves checking key components such as brakes, lights, tires, and fluid levels to identify any potential issues that could lead to safety hazards while driving. Before setting out on any trip, especially in commercial driving, prioritizing the vehicle's mechanical and safety systems is crucial to prevent breakdowns or accidents.

While reviewing the destination route, checking the fuel gauge, and cleaning the windows are all important steps in preparing for a trip, they do not address the immediate safety aspects of the vehicle in the same comprehensive manner as a full pre-trip inspection. Ensuring that the vehicle is mechanically sound and fully operational is the first priority, which makes the full pre-trip inspection the most critical initial step.