Discharge the vacuum in the servo
unit, with the engine stopped, by pressing and releasing the brake
pedal repeatedly and vigorously.With the brake pedal pressed, start the
engine without accelerating.Check that after a few seconds, the brake
pedal advances in accordance with the increase in pressure brought
about by the operation of the servo unit.Release the brake pedal and, without further action,
turn off the engine.After about 10 minutes operate the brake
pedal, and check that when it is pressed for the first time, it
lowers with assistance from the servo unit, and that subsequently
it gradually becomes harder.