What should happen during the park brake hold test at 1200 rpm?

During the park brake hold test at 1200 rpm, the expected outcome is that the bus should not move. This test checks the effectiveness of the parking brake by ensuring that it can hold the vehicle in place, even when the engine is running at a higher speed. If the parking brake is functioning properly, it will create enough force to keep the bus stationary despite the engine's increased power. This is crucial for safety, as a functioning parking brake prevents the vehicle from rolling away when parked, especially on inclines. The other outcomes, such as rolling forward, stalling, or reversing, indicate a failure in the parking brake system, which could lead to serious safety risks if not addressed.