Discharge the vacuum in the brake servo, with the engine switched off, by repeatedly pressing and releasing the brake pedal forcefullyStart up the engine without accelerating with the pedal depressed.After a few seconds, check that brake pedal is operating in accordance with the increase in pressure due to the action of the brake servo.Release the brake pedal and swith off the engine without operating the pedal again.After about 10 minutes with the engine switched off, operate the brake pedal and check that when it is operated for the first time the extent it is lowered corresponds to the brake servo and that the operation becomes gradually harder.