What should you do if the brakes fail while driving a commercial vehicle?

When faced with brake failure while driving a commercial vehicle, the appropriate course of action is to shift to a lower gear and utilize the emergency brake. Shifting to a lower gear helps to slow down the vehicle by using the engine’s resistance, which can be particularly effective in a commercial vehicle that may carry significant weight. This method takes advantage of the vehicle's mechanical system to decelerate safely without fully relying on brakes that have failed.

Using the emergency brake as a secondary measure can further assist in decreasing speed. It’s important to engage the emergency brake gradually to avoid causing the wheels to lock up, which could lead to a loss of control. This multi-faceted approach enhances the chances of safely bringing the vehicle to a stop.

In contrast, accelerating in an attempt to gain control could exacerbate the situation and lead to greater danger by increasing speed without a reliable braking system. Continuously using the horn is not a practical response to a failure of the brakes, as it does not contribute to stopping the vehicle. Steering into oncoming traffic is an extremely reckless maneuver that not only endangers the driver and the vehicle itself but also poses a severe risk to other road users.