Power Steering/speedo Cutting Out

[Potterhead7]

My boyfriend's 2004 Citroen C2 has a problem which the Citroen garage can't diagnose. The power steering and speedo randomly cut out for a while and then come back again while driving. The garage say they can only diagnose while its happening but it is literally impossible for my boyfriend or anyone to get the car to the garage at the drop of a hat! Last time we tried it had come back by the time we got there. I'm so worried he will have an accident, the roads he drives every day are so bendy. Does any one have any ideas? It has happened three or four times in the last three months.

[coastline taxis]

if you plug it into a lexia diagnostic then the fault will be in the stored codes.  its electronic steering pump on them and is linked to the speedo so to make the steering a bit heavier at higher speeds. without knowing any codes id start by looking at one of the abs sensors as it also doubles up as the speedo pick up as well.  it will be on one of the front wheels and although not 100% sure i think its on the passenger side