Technician A says that the vent port is open when the brakes are NOT applied. Technician B says that the replenishing port is open when the brakes are NOT applied. Which technician is correct?

Question

Quizplus · Accepted Answer

Both technicians are correct. The vent port in a brake system's master cylinder is open when the brakes are not applied, allowing the system to be at atmospheric pressure. Similarly, the replenishing port is also open when the brakes are not applied, allowing fluid to move back into the reservoir to compensate for any fluid displacement or to replenish fluid due to pad wear.

Technician a Says That the Vent Port Is Open When