What action actuates a dead mans seat brake and causes forklift to break?

The dead mans seat brake is actuated when the operator leaves the seat of the forklift. This is done by a pressure switch that is located under the seat. When the operator leaves the seat, the pressure switch is released, which sends a signal to the forklift's hydraulic system. The hydraulic system then actuates the brakes, which causes the forklift to stop.

The dead man's seat brake is an important safety feature that helps to prevent accidents. If the operator were to leave the seat while the forklift is in motion, the forklift would continue to move forward until it hit something, which could cause serious injuries or damage. The dead man's seat brake helps to prevent this from happening by automatically stopping the forklift when the operator leaves the seat.