just bought C5 2002 HDI diesil. done 46 miles and brake pedal gone hard, brakes not sharp,needs loads of pressure to stop car. pads are well worn could this be the cause?
Sounds like brake servo.press brake pedal 5 or 6 times and then hold it down without pause,start engine,if servo is working you should feel the pedal dip towards the floor.no dip?check hoses to servo and the function of the vacum pump.
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