Under what condition should a vehicle with a hydraulic system and hydro assist be rejected?

A vehicle with a hydraulic system and hydro assist should be rejected if there is no movement in the pedal when starting the engine because this indicates a potential problem with the braking system. The brake pedal is a crucial component that provides the driver with feedback and control over the vehicle's stopping power. If there is no movement in the pedal, it suggests that the hydraulic system is not functioning properly, which could be due to issues like a loss of hydraulic pressure, a failure in the master cylinder, or air in the braking system. Such conditions can severely compromise vehicle safety, making it necessary to reject the vehicle until the underlying issue is addressed.

A correctly functioning warning indicator lamp is not sufficient to ensure that the system is operating properly, as it may not indicate all underlying issues. A safe level of brake fluid is also not an indicator of operational integrity; even with sufficient fluid, other problems may exist. The steering wheel feeling loose pertains to the steering system rather than the brake system, so it does not directly relate to the functionality of the hydro assist braking system. Therefore, the absence of movement in the pedal is the key factor in determining that the vehicle should not pass inspection.