During a routine vehicle inspection, which set of lights cannot be checked all at once?

• A. Turn signals, brake lights, and 4 way flashers
• B. Headlights and taillights
• C. Parking lights and indicator lights
• D. Hazard lights and reverse lights

Answer: (A)

Testing exterior lights relies on using the right control for each function and observing the correct lights from the proper position. Turn signals, brake lights, and four-way flashers each need a different action: you flip the turn signal lever to activate the signals, press the brake pedal to illuminate the brake lights, and use the hazard switch to engage the four-way flashers. Because these actions are separate and can’t be performed or observed simultaneously in a single test, you can’t check all three together at once. In practice, you test them in sequence: verify turn signals, then brake lights, then hazard lights, ensuring each function works correctly.