What should a driver do in response to a low air warning signal when the engine is first started?

A low air warning signal indicates that the air pressure in the braking system is below the safe operating range. When the engine is first started, it is essential to wait for the air pressure to build up to the proper level before proceeding. This is critical not just for the safe operation of the vehicle, but also for the integrity of the braking system, which relies on sufficient air pressure to function correctly.

The process of building air pressure typically involves allowing the engine to run while watching the pressure gauge. It is crucial to ensure that the pressure reaches the manufacturer’s recommended levels before attempting to drive. This adherence to safety protocols is fundamental, as driving with inadequate air pressure can lead to brake failure, increasing the risk of an accident.

Other options do not prioritize safety. Continuing to drive without sufficient air pressure poses a significant risk, while shutting off the engine or consulting the manual would not address the immediate requirement of increasing air pressure necessary for safe vehicle operation. Consequently, waiting for air pressure to build up is the right response to ensure both driver and vehicle safety.