DEVICE FOR AVOIDING BRAKE DRAGGING IN A MOTOR VEHICLE CONFORMITY OF EMISSION TEST

The present application discloses a portable pressure relief device for avoiding brake dragging in a conformity of emission test of a motor vehicle, comprising: a vacuum pump (130); a power supply (120) capable of providing electric power to the vacuum pump (130); a controller (110) controlling power supply (120) to selectively provide electric power to the vacuum pump (130); and a hose (102) extending from an outlet of the vacuum pump (130), wherein an adjustable pressure-regulating valve (140) is connected in series in the hose (102), and an end of the hose (102) is provided with a connection port liquid-tightly and removably connectable to a brake fluid storage container (210) of a brake drive unit (200) of the motor vehicle. The present application also discloses a method for carrying out a conformity of emission test for a motor vehicle using said pressure relief device.