UK Car Repair: Vacuum brake pressure, brake master cylinder, rubber grommet

Question
My ford galaxy (05) has just failed its m.o.t because of low vacuum brake pressure. Can you help ?

Answer
low vacuum is usually the fault of the vacuum hose that goes from the inlet manifold to the brake master cylinder. check this black 15mm ish diameter hose for squashed looking parts. also check the rubber grommet at the master cylinder end of the hose for leaks by spraying water at it with the engine running. if the water is sucked up or rather slurped up its leaking.   replace the pipe or grommet or both as neccesary. if they are both ok have the master cylinder checked over by a decent garage. but it's only an 05, i doubt very much it could be the master cylinder.