CITROEN announced a problem with the C4, C4 Picasso, C5 & Dispatch II affecting a total of 20,063 vehicles.
In very rare circumstances the vacuum pump one way valve may not function correctly which could affect the level of braking assistance. Vehicles built from 21/12/2006 to 27/3/2009 are at risk.
The following remedial action is necessary to address this problem. Recall the vehicles that are likely to be affected to replace the brake vacuum pump one way valve.
If you think that your vehicle may be affected by this recall you should
find your nearest CITROEN dealer
who will be able to confirm whether or not your car is safe and arrange its free repair if necessary.
Source: UK Government's Vehicle and Operator Services Agency (VOSA).