What do the yellow warning lights on a tractor-trailer indicate?

The yellow warning lights on a tractor-trailer serve as a caution signal to other drivers and pedestrians. These lights indicate that there may be potential hazards or that the vehicle may be moving at a reduced speed. This warning is crucial in ensuring safety on the road, as it alerts others to exercise caution around the vehicle, particularly if it is experiencing issues or if it is about to stop or maneuver unexpectedly.

This function of yellow warning lights is standard across various vehicle types, as they are used universally to communicate caution without suggesting an immediate emergency, which would be indicated by red lights. The purpose of these lights is to promote awareness and safety, making it essential for drivers to recognize their significance while navigating roadways.