39. The parking and emergency brakes and the locking service brake of a road vehicle shall comply with the following standards:(1) the mechanism for the application of the parking brake shall be applied and released several times to make sure that the cables and linkages work freely; furthermore, the warning light shall come on when the brake is applied and turn off when released;
(2) the parking, emergency or service brakes shall prevent the vehicle from moving when fully applied on a flat surface, with the gearshift lever placed in the “drive” position in the case of an automatic transmission or, in the case of a manual transmission, in the highest gear that will allow a normal forward start, while the driver smoothly attempts to move the vehicle forward; furthermore, the wheels shall be completely free to turn where the brake is released;
(3) for a trailer or a dolly equipped with full pneumatic brakes, the brakes shall be fully effective where the pressure in the supply circuit is reduced to zero and the brakes shall release completely where normal pressure returns in the circuit; and
(4) the service brake shall be equipped with an adequate pressure accumulator, low pressure warning buzzer and pressure cutter in good working order.